Y-DNA and the Griffis Paternal Line Part Three: The One-Two Punch of Using SNPs and STRs

This is part three of a four part story on utilizing Y-DNA tests to gain knowledge or leads on the patrilineal line of the Griff(is)(es)(ith) family.

The One-Two Punch of Using SNPs and STRs 

SNP testing is the new age of genetic ancestry. This is primarily due to the technological advances associated with Y-DNA ‘string ‘ and ‘snip’ testing, the relatively straightforward interpretation of SNPs and dating of STR mutations, the increase of SNP discoveries and the explosive growth of Y-DNA database results.

STR testing and analysis represents the advances of genetic genealogy in the ‘early years’ of genetic gnealology (e.g. 2003 – 2014). However, both continue to provide unique strengths for genetic genealogical research.

During the ‘early years’ of Y-DNA testing, at the turn of the millenium, the popularity of obtaining Y-12, Y-25, and Y-37 STR tests increased. The results were generally reliable but oftentimes their results were mixed when compared with potential corroborating results obtained from traditional paper genealogical sources. A variety of statistical errors were documented such as “convergence” and “back mutation”. Through improvements in statistical analysis, the issues related to the statistical reliability of results were relatively increased and understood.

With Y-111 STR level testing common today, many of the accuracy problems noted in the first decade of the new millenium have been lessened. With more STR markers tested, it is possible to end up with matching or closely matching Y-DNA marker results in individuals who do not share a “recent” common ancestor on the male line. Convergence is more plausible in individuals belonging to common haplogroups. [1]

The use of SNPs are a fairly straightforward process of figuring out where a male lands on a current or possibly new branch of the Y-DNA haplotree. The results of SNP tests are intuitive and easy in analyzing a group of other testers because they uniquely identify the haplogroup branches of descent. You can group testers in branches of a haplotree depending on whether their tests confirm or predict specific SNP mutations that represent specific branches of the haplotree. 

In 2020, FamilyTreeDNA added 15,000 new high-coverage Big Y results to the Haplotree analysis, almost 5,000 academic results from present-day men in addition to thousands of ancient DNA results. This resulted in the addition of over 12,500 branches to “The Great Tree of Mankind”. Over 200,000 new unique SNPs were discovered. The growth rate has continued in the past two years. [2]

As indicated in illustration 1, the “One-Two” punch of testing involves using SNPs to provide a general location of Y-DNA testers on the Y-DNA haplotree based on nested haplogroups. Then, ‘the second punch’, if they are available, the use of Y-STR test results can help group test results within recent haplogroup branches and assist in analyzing potential individual matches. The analysis and comparison of individual Y-STR haplotypes can help delineate lineages and tease out branches within the haplotree, fine-tuning relationships between people within the tree.

Illustration 1: Using SNP and STR Results

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 2, 3 Oct 2019 https://www.youtube.com/watch?v=mhBYXD7XufI&t=355s
Click for larger view.

The accuracy of haplogroup prediction based on Y-STR haplotypes (as opposed to SNP values) depends mainly on the number of STR values that are tested. Haplogroup predictions based on low-resolution Y-12 to Y-25 STR test haplotypes have a low value of confidence and convergence can be a problem. For many older haplogroups, the Y-STR 25 to Y-STR 37 tests have an acceptable confidence level while for some young haplogroups that emerged with rapid diversification and expansion, the tests do not have enough to discriminate the correct sub-lineage with statistical confidence.

With the growth of next generation sequencing (NGS) tests and whole genome sequencing which report on both STRs and SNPs in a single test, the use of STR-based tests and the need for haplogroup prediction tools is in decline. [3] DNA companies, such as Family Tree DNA (FTDNA) provide NGS tests that predict haplogroup identification as well as identify potential matches with other DNA testers. However, the rub is judging how close are those identified potential matches. The ability to discriminate the accuracy of those matches is still an art form in this mathematically oriented field of genetic ancestry. While FTDNA has developed mathematical strategies to evaluate genetic distance between genetic matches, it is still useful to use other Y-DNA modeling tools to evaluate Y-DNA results.

While STR based haplogroup and genetic prediction tools may be on the decline, they are still helpful in refining and judging potential genetic matches as well as evaluating and discovering the general genetic patterns among the Y-DNA results. SNP data provides information on ancestral male lineage with precision because there are potentially millions of them for comparison and they mutate so slowly that random reversing (“back”) mutations are essentially nonexistent. Neutral SNPs (those not under selection pressure) provide a molecular clock that is good for millions of years that are useful to determine ancient ancestral splits and migrations. STR data, on the other hand, can provide guidance (not necessarily proof) of ancestry in more recent patterns because of their rapid mutation rates. [4]

I have used a number of Y-SNP and Y-STR tools and reports to help with my process of discovery (see Table One). In addition to the FTDNA reports, I have used tools created by individual genealogists that provide creative renditions of the data. For example, assuming there are sufficient testers to compare STR results, mutation history trees and dendrograms can be created illustrate genetic distance and graphically reveal genetic branches from hundreds of years back to the recent past ( fine-tune the smaller branches, ‘twigs’, in a genetic tree).  The STR tools are highly effective if used in tandem with SNP data and traditional genealogical information (hence, “the one-two punch”). 

Table One : Y-SNP & Y-STR Tools Used in Y-DNA Research

STR / SNP ToolCreatorDescription
SNP TrackerSpencerCreates a map based on SNP data which traces paternal line from human origins 
Britain & Ireland SNP & Surname MapperSpencerBased on Surname or SNP input, provides historic British census countywide data and maps
Y STR Clustering and Dendrogram DrawingSpencerGenerate circular/ linear dendrograms from FTDNA data. The tool provides quick and incisive graphic depictions of relationships between test kits on STR values and genetic distance.
FTDNA Admin UtilitiesSpencerSNP Breadcrumbs; Find Common Ancestor;  Export Tree Text; ISOGG Y-SNP Synonyms; 
Still Another Phylogeny Program SAPPVanceImport Y-STR and Y-SNP data to create phylogenetic tree. This is a great program to use in conjunction with SNP results that group test results in a major SNP rant. The tool can then map out possible lines between testers based on STR values.
Y-DNA Matches FTDNALists Matches based on Y 12, 25, 37, 67, 111, and Big Y 700 STR tests
Y-DNA Haplotree FTDNALists haplotree based on confirmed terminal haplogroup, lists all SNPs tested positive or presumed positive
Y-STR ResultsFTDNALists the specific test results for Y-111 and Big Y 700 STR tests
Big Y BlockTM TreeFTDNAA vertical-block visual diagram of Y-DNA haplotree showing Big Y testers. This tool helps you visualize how the paternal lineages are related to each other. Also provides Paternal Countries of Origin and other information.
Haplogroup StoryFTDNAPart of FamilyTreeDNA Discover™ series reports. Based on SNP input, provides estimated time of when haplogroup was born. when did your paternal ancestor live and where are his descendants found today.
FTDNATiP™ ReportFTDNAProvides Genetic Distance estimates for potential Y-DNA STR matches

While STR tests are used by individual testers to discover possible Y-DNA genetic matches with other testers, the results of STR tests can also provide insights into macroscopic demographic properties that can shed light on lineages and clans – well before the time of surnames. Y- STRs have a time window that runs back to the late Bronze Age.

STRs … tell us about demography — specifically about bottlenecks and subsequent expansions, namely “founder events.” While SNPs tell us when they were created, STRs tell us about when the population burgeoned after a founding mutation. That SNP and STR clades have a fundamentally different interpretation has caused considerable confusion, but once understood, the methods are very useful complements.” [5]

STRs have been viewed as having limited use in estimating dates beyond about 50-100 generations. However, there have been studies that indicate STR data can be utilized to for genealogical analysis into the Paleolithic era. [6]

Support from Y-DNA Working Group Projects

Coupled with the Y-STR tests, Family Tree DNA offers a wide variety of Y-DNA Group Projects to help further research goals. The group projects are associated with specific branches of the haplotree, geographical areas, surnames, or other unique identifying criteria. Based on their respective area of focus, the research groups have access to and the ability to compare Y-DNA results of fellow project members to determine if they are related. These projects are run by volunteer administrators who specialize in the haplogroup, surname, or geographical region that one may be researching. 

FTDNA supports a network of over 11,000 Group Projects to assist and support individuals who are interested in pursuing information about a specific topic related to their genealogy. The projects base research on members’ DNA testing results and to join a project one must test with, manage, or transfer results to FamilyTreeDNA. These working group projects are based on Y-DNA or mtDNA test results and are related to a surname, geographical area of interest, or haplogroup. Illustration 2 provides a graphic example of how a typical Haplogroup project manages Y-SNP and Y-STR test results. [7]

Illustration 2: Structure of a Typical Haplogroup Project

Source: J David Vance, The Genealogist Guide to Genetic Testing, 2020 Chp 10 Figure 10.4
Click for Larger View.

Typically, one of the group project administrators will review your test results (STRs and well as SNPs), known matches and ancestry. The work group administrators will then place your tests in a subgroup within the project. The subgroups are usually based on individuals who have common actual or predicted lower level SNPs. They can then help in calculating the modal haplotype for STRs for the smaller subgroup of testers which can help with the development of a mutation history tree.

For my research on the Griff(is)(es)(ith) family, I joined five Y-DNA Family Tree DNA based projects to assist in my ongoing research:

  1. The GRIFFI(TH,THS,N,S,NG…etc) surname project is intended to provide an avenue for connecting the many branches of Griffith, Griffiths, Griffin, Griffis, Griffing and other families with derivative surnames. The Welsh patronymic naming system, practiced into the latter 18th century, makes this task more difficult. Evan, Thomas, John, Rees, Owen, Williams and many other common Welsh names may share common male ancestors. (820 members as of the date of this article).
  2. The G-L497 project includes men with the L497 SNP mutation or reliably predicted to be G-L497+ on the basis of certain STR marker values. The L-497 is a branch or subclade of the G-haplogroup (M201+). The project also welcomes representatives of L497 males who are deceased, unavailable or otherwise unable to join, including females as their representatives and custodians of their Y-DNA. The primary goal of the project is to identify new subgroups of haplogroup G-L497 which will provide better focus to the migration history of our haplogroup G-L497 ancestors. (2,326 members as of the date of this article.)
  3. The G-Z6748 project is a Y-DNA Haplogroup Project for a specific branch that is a more recent, ‘downstream’ branch from the L-497 branch of the G haplotree. It is a project work group that is a subset of the L497 work group. The G-Z6748 subclade or brand appears to be a largely Welsh haplogroup, though extending into neighboring parts of England. (33 members as of the date of the article)
  4. The Welsh Patronymics project is designed to establish links between various families of Welsh origin with patronymic style surnames. Because the patronymic system (father’s given name as surname) continued until the 19th century in some parts of Wales, the working group is not limited to a single surname. (1,572 members as of the date of this article.)
  5. The Wales Cymru DNA project collects the DNA haplotypes of individuals who can trace their Y-DNA and/or mtDNA lines to Wales. Tradition holds that the Celts retreated as far west in Wales as possible to escape invading populations. This project seeks to determine the validity of the theory. This project is open to descendants from all of Wales. (842 members as of the date of this article.)
  6. The New York State DNA project is a project I recently joined. It is open to all men and women who live in New York State or who can trace their ancestors to New York State. (There are over 3,000 members in this project.)

Two of the six working groups, the G-L497 and the G-Z6748 Haplogroup projects, have been notably helpful in my research with genetic ancestry. The G-L497 working group has a large contingency of test results and a relatively large number of group administrators to help group participants in their research efforts. The administrators of the L-497 working group also provide a wide range of links to reference material associated with the L-497 haplogroup.

The G-Z6748 Haplogroup is a relatively new group and is an offshoot of the L-497 work group. It is a very small group of FTDNA testers that can trace their G- Haplogroup Y-DNA to the British Isles, particularly in the area of Wales.

SNPs, Haplotrees and Haplogroups: Deep Ancestry and Lineages

Illustration 3 is an highly simplified example of a branch in a Y-DNA haplotree that shows SNP mutations between generations of descendants. It provides a simple approach for understanding the development of the Y-DNA haplotree with SNP data. [8]

The male at the top of the tree exhibits “mutation one” (M1). This means all of his descendants will exhibit the same mutation. This same nucleotide could change again but the odds are it will not change and it will continue through his lineage. In subsequent generations other male descendants may exhibit single nucleotide changes in other areas of the DNA strand but will continue to exhibit the M1 mutation.

Illustration 3: Example of SNP Mutations and Genealogical Paths

Source: An adaptation of illustration 3.9 found in J David Vance, The Genealogist Guide to Genetic Testing, 2020.
Click for larger view.

In this illustration, we have two branches in the genetic haplotree where on one side a descendant exhibits “mutation 5” and on the other branch a descendant exhibits “mutation 2”. Each of their respective male descendants will respectively exhibit or test positive for M1 / M7 (in the left branch) and M1 / M2 (in the right hand branch) SNP mutations respectively. Descendent 1, at the bottom of the illustration, will test positive for M1, M5. M6. and M7 mutations and negative for M2, and M4 mutations. Descendants 2 and 3 will test positive for M1, M2 and M4 and negative for M5, M6, and M7. Descendant 3 will test positive for M1 and M2 and negative for M4 through M7.

The key to this exercise is one can trace the SNP mutations through successive genetic lines thereby creating a genetic family tree. SNPs are referred to as M1 through M7 in the illustration. Obviously, SNP testing is a bit more complex. SNPs are actually named with a major capital letter(s) and then with a number. [9]

haplogroup, as previously indicated, is a genetic population group of people who share a common ancestor on the patriline or the matriline. Top-level haplogroups are assigned letters of the alphabet and deeper branches or subclades are labeled depending on what different nomenclature system is used.

The above illustration also greatly simplifies how many SNPs are associated with major branches in the haplotree and does no discuss the number of years between identified branches in the haplotree. Many of the haplotree branches actually represent mutations in various male descendants spanning thousands of years. Also, each branch is typically represented by an accumulation of SNPs that define or are associated with a given branch of the tree.

Illustration 4 below provides a graphic depiction of the relationship between SNPs and haplogroups within the Y-DNA Haplotree. The illustration uses the G haplogroup, as an example. The Griff(is)(es)(ith) paternal line is a part of the G-M201 haplogroup.

Illustration 4: SNPs in Relation to the Haplotree and Haplogroups

Revised illustrations originally in an online presentation from J David Lance
Click for larger view.

Illustration 5 provides a high level view of the structure of the Y-DNA haplotree. The Griff(is)(es)(with) Y-DNA line of descent is part of the Y-DNA G haplogroup that emerged approximately 45,000years ago.

Illustration 5: High Level View of the Y-DNA Haplotree

Source: Slide 30 of a powerpoint presentation:J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 2, 3 Oct 2019 https://www.youtube.com/watch?v=mhBYXD7XufI&t=355s
Click for Larger view.

The major Eurasian Y-DNA-haplogroups (E1b, G2a, I1, I2, J1, J2, N, O, R1a, R1b, etc.) formed over tens of thousands of years, typical African Y-haplogroups like A, B and C have even deeper roots.

Haplogroup G descends from haplogroup F, which is thought to represent the second major migration of homo sapiens out of Africa, at least 60,000 years ago. While the earlier migration of haplogroups C and D had followed the coasts of South Asia as far as Oceania and the Far East, haplogroup F penetrated through the Arabian peninsula and settled in the Middle East. Its main branch, macro-haplogroup IJK would become the ancestor of 80 percent of modern Eurasian descendants.

Haplogroup G formed approximately 40-50,000 years ago as a side lineage of haplogroup IJK. Haplogroup G had a slow start in terms of migration, evolving in isolation for tens of thousands of years, possibly in the Near East, cut off from the wave of migration of Eurasia.

Paleolithic lineages (roughly 2.5 million years ago to 10,000 BCE) that underwent serious population bottlenecks, for thousands of years sometimes, have a series of over one hundred defining SNPs in their root branches The root branch (M201) of the G haplogroup of which the Griffis lineage is a descendant has over 300 defining SNPs, confirming that this paternal lineage experienced a bottleneck before splitting into haplogroups G1 and G2 (see footnote 18).

The sub-branch G1 might have originated around modern Iran at the start of the Last Glacial Maximum (LGM), approximately 26,000 years ago. G2 developed around the same time in West Asia. At that time humans in Europe were part of earlier haplogroups and were hunter-gatherers and living in small nomadic or semi-nomadic tribes. Members of haplogroup G2 appear to have been closely linked to the development of early agriculture in the Fertile Crescent, starting 11,500 years before present. The G2a branch expanded to Anatolia (modern day Turkey), the Caucasus and Europe, while G2b diffused from Iran across the Fertile Crescent and east to Pakistan. [10]

Organizational Differences Between Y-DNA Haplotrees

Since 2002, the nomenclature and structure of the Y-DNA haplotree has evolved with various modifications. As indicated in part one of this story, there are four major Y-DNA haplogroup trees managed by various groups. The most widely used versions are managed by (1) the DNA company Family Tree DNA (FTDNA), and two DNA research organizations : (2) YFULL, and (3) the International Society of Genetical Genealology (ISOGG). Each of the companies or organizations have different representations of the tree.  They also do not uniformly use the same branches or SNP names. [11]

For Y-DNA, a haplogroup may be shown in the long-form nomenclature established by the Y Chromosome Consortium, or it may be expressed in a short-form version, using a deepest-known SNP. [12] Since 2012 many scholars, companies and genetic genealogists agreed to use what is called a Shorthand – SNP nomenclature Haplotree system to avoid naming confusion for the future. Family Tree DNA also merged to this system. [13] An example of this nomenclaure is found in Illustration 6 for the G haplogroup. The highlighted areas in the illustration trace the Y-DNA line for the Griff(is)(es)(ith) family.

Illustration 6: Example of Basic Hierarchy for Shorthand System Nomenclature for Beginning of the G Haplogroup

The differences between the three primary Y-DNA haplotrees is apparent when comparing my Y-DNA SNP results. Changes in the haplotrees can occur frequently based on incorporating new Y-DNA test results. New test results are not uniformly accepted by each of the three organizations. The differences between the three haplotrees are based on the nomenclature of the specific haplotree, what SNPs are accepted by a particular haplotree, and what SNPs are selected from the same equivalent block of SNPs to identify a particular branch of the Y-DNA haplotree. It makes you cross-eyed trying to follow all of this.

FTDNA Designation of my Terminal SNP

At this point in time, it is noteworthy that my test results put me on the cutting edge of new discoveries in genetic genealogy for the G haplogroup in the British Isles. as new Y-DNA test results are incorporate into the Haplotree, they can have an impact on my position in the Haplotree. Also, not all of FTDNA have been incorporated into the results of the YFULL and ISOGG haplotrees. In the FTDNA haplotree, as reflected in illustration 7 below, my SNP and STR results have been designated as a private SNP haplotree branch, as a subclade off of branch BY211678 along with another subclade branch G-FT119236.

Based on the results of my Big Y-700 FTDNA test, my Terminal SNP (branch or subclade) is G-BY211678. Basically, this means I am the descendant of a male who is the most recent common ancestor (MRCA) of this genetic line who was born ‘around’ 1500 CE with 95 percent statistical confidence variance of being born between 1283 CE and 1684 CE. [14]

Illustration 7 represents the ‘smallest branches and leaves’ of my Haplotree path. The data is from FTDNA’s Block Tree of Big Y test kits. It is a few branches down from the G-P303 branch and the L-497 branch which are most frequent and widespread G sub-haplogroups in Europe. The sub-clades of P-303 have more localized distribution with the U1-defined branch largely restricted to Near/Middle Eastern and the Caucasus and the L497 lineages essentially occur in Europe where they likely originated. [15] The man whose genetic SNP mutations created the G-6748 branch was born around 700 CE.

Illustration 7: Rendition of Portion of FTDNA Big Y Block TreeTM of G- Haplogroup Starting with the G-Z6748 Sub-Branch

Source: FTDNA Big Y Block Tree Data as of 22 Feb 2022
Click for larger view.

Looking at the haplotree from the view of testing for specific SNPs, as indicated Illustration 8, from G-Z6748, the following branches G-Y38335 > G-FGC486 > G-Z40857 > G-Y132505 trace down to G-BY211678. Since I have tested positive for this SNP, FTDNA has provided a new name for this terminal SNP in 2020: G-BY211678. I am presently the only one that is directly tied to this public SNP. The others have tested for a new downstream branch from this SNP and have formed their own subbranch G-FT119236.

Illustration 8: FTDNA Big Y 700 Y-DNA Test Confirmed Terminal Branch for James Griffis

Source: FTDNA Time Line | Click for Larger View.

The direct match to the FTDNA newly formed branch BY211678 is not documented in the International Society of Genetic Genealology (ISOGG) or the YFULL haplotrees. Both of these organizations consider my terminal SNP as a private (individual) SNP variant at this moment in time. A new branch is not recognized by ISOGGZ or YFULL until at least two individuals are found to have similar positive test results for the SNPs. However, one step up the haplotree branches, ISOGG has documented G-Y132505 which in long form is G2a2b2a1a1b1a1b1a2b. A designation that one certainly cannot remember! The YFULL haplotree also lists G-BY211678 as a SNP variant under the G-Y132505 branch rather than a subclade branch in the haplotree under G-Y132505. [16]

Given the number of newly discovered SNPs that have formed new branches in the Y-DNA tree, many of these new variant SNPs are yet to be confirmed by ISOGG and YFULL. Most of these new FTDNA SNP variants are considered as private SNPs by the other organizations unil other testers test positive or negative for the SNP. Accordingly, their names will reflect FTDNA names and numbers for the newly identified SNPs.  

In the FTDNA haplotree, the ‘Y132505″ branch, is two branches above my terminal SNP position. As of January 2023, my termnial SNP position has been labeled FT48097. The ‘FT’ is an ISOGG based prefix referring to a result from FTDNA Big Y testing. The Y132505 branch is found in the FTDNA, YFULL, and ISOGG haplotrees. The “Y” refers to the source of this SNP’s discovery (YFULL team using published and commercial next generation testing results).

Illustrations 9 and 10 reflect the relative position of my SNP/STR results in the YFULL and ISOGG haplotrees.

Illustration 9: YFULL Haplotree G-Y132505 Branch

Source: YFULL Y-DNA Haplotree. Click for larger view.

The YFULL haplotree defines the BY211678 SNP as a private individual variant as opposed to a sepate subbranch to G-Y132505.

Illustration 10: ISOGG Haplotree G-Y132505 Branch

Source: Click for larger view.

The ISOGG haplotree portrays G-Y132505 as the terminal SNP, with no mention of G-BY211678 or G-Y132506.

Equivalent SNPs and Y-DNA Haplotree Branches

Equivalent or variant SNPs are mutations observed in the same block of SNPs for a specific branch or haplogroup. They are equivalent in the sense that they can all be used to describe a haplogroup branch since it is impossible to define the chronological order (time of occurrence) of the SNPs in one haplogroup. [17]

Many haplogroups and subclades in the Y-DNA Haplotree are defined by more than one SNP. All of the Y-DNA public haplotrees are developed from research of ancient human artifacts and by the continuous analysis of test results of men completing Y-DNA tests and developing a SNP mutation history that shows how their ancestors branched from each other. Because many branches have died out long before modern day, any group of tested men will only show a fraction of all branches that actually occurred. Picking a SNP to identify a given branch may not be straightforward if there are more than one available SNP since the chronological order of each SNP may not be known.

Nearly every SNP on every public Y-DNA haplogroup tree is just one label for a block of equivalent SNPS. The equivalent SNPS are different physical mutations so they represent successive mutational genetic generations of men.  They are only equivalent as long as the haplotree remains the same and there are no discoveries of descendants associated with a given SNP to differentiate the chronological order. They represent a long series of generations of paternal ancestors who have no other descendants living today who have tested their Y-DNA except for the different groups who descend from different ancestors at the bottom of an equivalent block of SNPS.  Any new tester may create a previously unknown branch which descends from a different ancestor inside this long series of generations or block of equivalent SNPs. 

“Y-DNA and mtDNA lineages go extinct all of the time. About 80% of all lines have gone extinct through most of recorded history; this is how surnames vanish… . A ‘founder’ event occurs when a line almost goes extinct but then recovers, which leaves a clear imprint on descendants’ DNA.” – Rob Spencer

Surnames and Y lineages go extinct far more often than most people realize. However, everyone probably has family experiences of having sisters, bothers, aunts or uncles with no children, or relatives with daughters but no sons — which is exactly how Y-DNA line extinction happens.

Until the mid-1800’s (with the notable exception of colonial North America), any given Y lineage had a 70-75% likelihood of going extinct within about 5 generations. [17a]

This has a strong impact on Y DNA genealogy. For the rarer haplogroups which includes the Griff(is)(es)(ith) genetic line (e.g. Haplogroups E, G, T, J are the rarer lineages in Europe), it is not unusual to find that one’s Y SNP lineage ‘ jumps’ from the Bronze Age to the present without any haplogroup branching. Males were no doubt born all along the way but with low numbers and with few branches, many died out before anyone would survive to take a DNA test. Illustration X provides a graphic depiction of the probability of Y-DNA extinction base on general historical time periods. [17b]

Illustration 10a : Probability of Y-DNA Lines of Extinction by Time Period

Source: Rob Spencer, Check out Rob Spencer’s Extinction Simulator. This simulator will help you visualize how frequently human lineages go extinct across different historical time periods. 

Generally speaking the number of accumulated SNPs between a haplogroup and its direct subclade correlates roughly to the number of genetic generations elapsed between the two branches. It is highly unlikely that only one genetic generation (e.g. 33 years) can be used as a multiplying factor for gaging time between two branched based on the number of equivalent SNPs associated with the older branch.

Illustration 10 provides an example of some of the major branches or subclades (SNP mutations ) of the G haplogroup of which the Y-DNA of Griff(is)(es)(ith) family can be traced. The illustration also indicates the number of variant or equivalent SNPS associated with a particular branch. For a list of all the equivalent SNPs in the Griff(is)(es)(ith) line, see footnote [18]. Illustration 10 also indicates the approximate date of when the branch occurred (e.g. when a male exhibited a specific SNP mutation).

Illustration 10: SNP mutations and the Patrilineal Line for Griffis Family

Adapation of Illustration from J David Vance, The Genealogist Guide to Genetic Testing, 2020 , page 23. Click for larger view.

The Griff(is)(es)(ith) Patrilineal Y-DNA Line: The Big Picture

Based on the results of my Big Y 700 SNP test from FamilyTree DNA, Table Two provides a general outline of the major SNPs that represent major mutations in my Y-DNA line of genetic ancestors. Each of these SNPs represent a common ancestor that had a Unique Event Polymporhism (UEP) which represents the beginning of a new Y-DNA branch in the haplotree. The table traces major mutations from the beginning of of the G Haplogroup all the way to my most recent common Y-DNA ancestor G-BY211678 through the G Haplogroup.

Table Two: Griff(is)(es)(ith) Y-DNA Lineage on the Family Tree DNA (FTDNA) Haplotree

FTDNA
Y Branch
Subclade
Main SNPs
Age
Estimate
Time
Passed
(Years)
From
Preceding
Branch
Phylo-
genetic
Sub-
clades
SNP
Branch
Variants /
Equiv-
alent
SNPS
Down
Stream
Branches
~ 2022
Number of
Descendants
in FTDNA
Database
01-14-22
GHIJK-
F1329
46,000
BCE
< 1,0002214,467
G-M20126,000
BCE
20,00023181,7319,658
G-L8924,000
BCE
20,00021121,6236,133
G-L15620000
BCE
4,0002621,6216,103
G-P1516000
BCE
4,0002571,5415,748
G-L125916000
BCE
< 1,000271,4035,007
G-L3013000
BCE
3,0002471,2264,519
G-L14112000
BCE
1,0002141,0183,806
G-P3039700 BCE2,3003389593,629
G-L1409000 BCE7003149073,298
G-PF33468950 BCE< 100218963,167
G-PF33458900 BCE< 1001138893,145
G-L4975300 BCE3,6002494561,747
G-CTS97374400 BCE9002124491,632
G-Z18173000 BCE3,0002154361,575
G-Z7272450 BCE550384311,464
G-FGC4772100 BCE3005252113
G-Z6748700 CE2,8002292249
G-Y38335750 CE< 100221243
G-Z408571000 CE250351941
G-Y1325051250 CE2503227
G-BY2116781500 CE2502415
Source: Family Tree DNA, Data Jan 2022

The following provides an explanation of the information found in Table Two.

Column One: Name of ancestral haplogroup in the FTDNA Y-DNA haplotree.

Column Two: Age estimate is the estimated time when the most recent common ancestor of this lineage was born. The date is an estimate based on genetic data. The date is within a 95 % statistical confidence level that the most recent component ancestor of all members to each of these specific haplogroups was born at the stated time. The figure is the most likely estimate in that 95% statistical band and rounded to the nearest 100 or 50.

Column Three: Time passed is the elapsed time between a given haplogroup and its ancestral haplogroup. A large number can suggest a small population size or a bottleneck, causing only one lineage to survive for a long time. 

Column Four: Phylogenetic subclades refers to the number of immediate descendants with UEP SNP mutations. A large number indicates a rapid expansion event.

Column Five: SNP branch variants refers to the number of Equivalent or variant SNPs mutations observed in the same block of SNPs for a specific branch or haplogroup. They are equivalent in the sense that they can all be used to describe a haplogroup

Column Six: Number of Downstream branches refers to the number of subclades below this paerticular branch in the tree.

Column Seven: Number of tested modern descendants is the number of present day DNA testers confirmed to belong to this haplogroup. 


One can get a sense of the general characteristics of genetic change at the macroscopic level in a given haplogroup line of descent by reviewing specific aspects of when major SNP mutations occurred and the elapsed time between a given haplogroup and its ancestral haplogroup. In general, the Y-DNA line for the Griff(is)(es)(ith) paternal line suggests an historical line of descent that encountered a high rate of male line extinction. Look at the numbers in column 4. The number of new genetic branches are relatively small. Look at the numbers in column 3. The number of years between branches are large. I have identified the figures in bold in column 3.

The G haplogroup and my specific genetic line of descent survived a succession of ‘genetic hardships’ for survival. With the exception of two points in time, the average number of new phylogenetic subclades or the number of immediate descendants with UEP SNP mutations typically reflected only 2 new branches. Despite having a number of equivalent SNPs at each of the major branches, there were not many genetic branches that survived. Around 8,900 BCE the subclade BCE G-PF3345 had 11 branches and around 2,100 BCE the branch G-FGC477 had 5 subclades, suggesting some genetic proliferation at this time period.

Because many branches have died out long before modern day, many of the branches of the haplotree will only show a fraction of all the branches that actually occurred. The extinction of Y-DNA lines is the result of a number of cultural (war, patrilineal competition), environmental (famine, disease, climate), and biological factors (no male offspring) and is one facet of the overall growth, contraction and expansion of human population.

“Three major movements of people, it now seems clear, shaped the course of European prehistory. Immigrants brought art and music, farming and cities, domesticated horses and the wheel. They introduced the Indo-European languages spoken across much of the continent today. They may have even brought the plague. The last major contributors to western and central Europe’s genetic makeup—the last of the first Europeans, so to speak—arrived from the Russian steppe as Stonehenge was being built, nearly 5,000 years ago. ” [19]

While each of these 3 waves of migration were composed of a mix of genetic haplotypes, each were represented by one or two major genetic haplogroups.

Illustration Eleven: The Three Waves of Human Migration to Europe

Source: Andrew Curry, The first Europeans weren’t who you might think, National Geographic, Sept 2019 Click for Larger View

Illustration 12: DNA Legacy of Europe

Source:Andrew Curry, The first Europeans weren’t who you might think, National Geographic, Sept 2019| Click for Larger View

About 45,000 years ago, the first modern humans ventured into Europe. The first wave of modern Europeans lived as hunters and gatherers in small, nomadic bands. They followed the rivers into western and central Europe. 45,000 years ago. Their DNA indicates they mixed with the Neanderthals. As Europe was gripped by the Ice Age, the modern humans inhabited the ice-free areas of Southern Europe. About 14,500 years ago, as Europe began to warm, humans followed the retreating glaciers into Northern Europe.

The second wave is associated with the migration of Neolithic farmers from the Anatola region. The G-Haplogroup was part of this second wave. They brought not only their DNA but sheep, cattle and wheat to Europe. Within a thousand years the “Neolithic revolution” spread north through Anatolia and into southeastern Europe. By about 6,000 years ago, there were farmers and herders all across Europe.

The third wave, which is predominantly represented by the Yamnaya and are part of the R-Haplogroup, emanated from the Steppes. By 2800 B.C, archaeological excavations show the Yamnaya had begun moving west out of the Steppes. As they proceeded westward, things stated to change. All across Europe, thriving Neolithic settlements shrank or disappeared altogether. The dramatic decline has puzzled scientists from various fields of study and there are various hypotheses that attempt to explain this genetic decline and replacement by the R-haplogroup.

Within a few centuries, the presence of Yamnaya DNA had spread as far as the British Isles. In Britain, similar to other European areas, hardly any of the farmers who lived in Europe survived the onslaught from the east. Until then, farmers had been thriving in Europe for millennia. The second wave of human had settled from Bulgaria all the way to Ireland, often in complex villages that housed hundreds or even thousands of people.

One of many possible theories of the dramatic decline of G-Haplogroup along with other genetic haplogroups associated with the Neolithic farmers is the discovery that some of DNA samples of the Yamnaya contained an early form of Yersinia pestisthe plague microbe that killed roughly half of all Europeans in the 14th century. [20] Unlike that flea-borne Black Death, this early variant had to be passed from person to person. The steppe nomads apparently had lived with the disease for centuries, perhaps building up immunity or resistance. Similar to the history of smallpox and other diseases that ravaged Native American populations, the plague, once introduced by the first Yamnaya, might have spread rapidly through crowded Neolithic villages. That provides a plausible explanation of collapse and the rapid spread of Yamnaya DNA.

While it is a cogent explanation, this theory begs the question of whether there is evidence to substantiate the presence of plague DNA in ecological finds. It has only recently been documented in ancient Neolithic skeletons, and so far, no one has found anything like the plague pits full of diseased skeletons left behind after the Black Death. If a plague wiped out most of Europe’s Neolithic farmers and the G-Haplogroup, it left little trace.

There is strong evidence of major founder events at the end of the Neolithic period. It has been stated that two-thirds of all European men from the R-haplogroup descend from just three ancestors who lived in the late Neolithic.  [21] The G-Haplogroup migrated into Western Europe prior to the R-Haplogroup but had similar genetic / demographic impacts at two different time periods, as mentioned above.

Changes in genetic variation are driven not only by genetic processes, but can also be causes or be correlated with cultural or social changes. An abrupt population bottleneck specific to human males has been inferred across several Old World (Africa, Europe, Asia) populations between 5000–7000 BP (5,000 BCE – 3000 BCE). [22]

Combining anthropological theory, population genomic studies and mathematical models, a number of studies have proposed a general sociocultural hypothesis involving the formation of patrilineal kin groups and intergroup competition among these groups as having led to a reduction of Y chromosomal diversity. This reduction was much greater than the reduction in male population size, while keeping the female population size stable.. Various analyses of DNA data show that this sociocultural hypothesis can explain the inference of the population bottleneck in this time period. [23]

Using Rob Spencer’s SNP Tracker to provide illustrative examples of the migratory paths of various haplogroups [24], I compared (Illustration 13) the migratory path of my haplogroup (part of the second wave) with the migratory path of one of the major R-haplogroups, the R1b-M269 haplogroup (part of the third wave). Why compare my haplogroup with this uniquely named haplogroup? The R1b-M269 is a branch of the R-haplogroup that has been associated with the Beaker Culture that was prominent in Western Europe and eventually migrated to Scotland.

Illustration 13: Estimated Migratory Paths for R1b-M269 Haplogroup and the G-BY211678 Haplogroup

Click for Larger View.

As you can see in the illustration, there is some geographical overlap with the two migratory paths in Western Europe of these two haplogroups. My hunch, (“I did stay at the Holiday Express“) is that my Haplogroup descendants were part of the second wave migration into Europe and eventually were in areas now considered as Germany between 5000 BCEto 2350 BCE and then migrated further westward to what is now northern France and the migrated to the British isle.

As discussed in Part Two of the story, cultural and genetic genealogy are two logically distinct aspects of genealogy. Similarly, various migratory patterns associated with Haplogroups do not necessarily imply that they coincide with cultural geographical patterns or movements. Migratory patterns of Y-DNA Haplogroups undoubtably contained a mix of haplogroups. Y-DNA haplogroups also were represented in various historical cultures. Many cultures invariably contained genetic mixtures of Haplogroups at various periods of time.

Illustration 14 provides a map that ties Y-DNA haplogroups with early Bronze age cultures that were present in Europe. [25] This approximates the time period where I believe the Griff(is)(es)(ith) G-Haplogroup line may have intersected with the R-Haplogroup and were both part of the Beaker and Corded Ware Cultures.

Illustration 14: Associations of Early Bronze Age Cultures with Y-DNA Haplogroups

Click for Larger View.

The Griff(is)(es)(ith) patrilineal descendants may have encountered the third wave’ of European migrants in the northwest Europe perhaps around 2,500 BCE . They survived a possible plague as well as any possible socio-cultural kinship battles and assimilated into the evolving culture of the times and remained in Northern/Western European area until around or before the Norman invasion (1100 CE). At that time it would appear our descendants migrated to the British Isles, utlimately to Wales.

Using STR Results to Clarify Lineages Before the Advent of Surnames

As stated, the analysis of SNP and STR test results provide a one-two punch in mapping Y-DNA lines of descent. As reflected in the above discussion, the use of SNP data is relatively straightforward. Your placement on the Y-DNA haplotree is based on which SNPs test positive in your Y-DNA tests.

There are a number of Y-DNA tools that can be used to analyze Y-DNA STR results. [26] A mutation history tree portrays the likely haplotype of a most recent common ancestor and the most likely series of STR mutations which occurred in the descendant branches to arrive at the haplotypes of the present day testers (ancestral haplotype).

Comparing STR test results require “more mathematical work” to be useful, and are highly dependent on the number STRs tested.  Since STRs mutate at variable rates more frequently than SNPs, one must eliminate the effects of convergence and the mathematically incorporate the differential effects of mutation rates on STR markers.

” . . . (A)ll STR data — Y12 to Y111 — are very reliable for exclusion: you can say with very high confidence that two people are not related if there is a strong mismatch of their STR patterns. This is the forensic use of DNA: it’s very powerful in proving innocence while less decisive about proving guilt.” [27]

FTDNA provides a number of Y-DNA tools and organizational strategies for analyzing Y-DNA results that facilitate “the two-punch process”. SNP results are first used to figure out where one is situated in the Y-DNA haplotree. Depending on the type of Y-DNA tests that are completed, a tester can determine their relative position on the Y-DNA haplotree. The more detailed the test, the more accurate and reliable are the results of placement on the haplotree. The Y12 through Y67 tests will give you a general idea of your haplogroup while the Y111 test will place in one of the more defined branches of the tree. The Big Y700 test will identify the specific ‘twig’ or leaf’ of the tree. STRs can then be used to compare testers that are grouped by haplogroup to discover possible genetic matches or fine tune the branches of the haplotree.

This is where things can get interesting in terms of potential genetic matches and teasing out one’s genetic lineages before the use of surnames.

For genealogy within the most recent fifteen to twenty generations (about 500 to 660 years ago), STR markers help define paternal lineages and patterns around the advent of the use of surnames. For Welsh descendants the number of generations will be closer in terms of when surnames were routinely used. STR analysis is an excellent approach to document genetic lineages before the use of surnames and into a period in which surname of genetically matched test kits could be different. For patrilineal lines a descent with Welsh surnames, this is important. The likelihood of finding genetic matches with test kits associated with different surnames is highly likely! [28]

Illustration 13: Genetic Matches and Surnames

Click for Larger View.

Y-STR analysis can also identify patterns which suggest the structure of American colonial families. Typically there will be a gap of 10 or more genetic generations followed by an expansion of family ties. [29].

Illustration 12: Spot the American Immigrant Families

Click for Larger View.

The information in Table Three displays Y-Chromosome DNA (Y-DNA) STR results for testers in the L-497 Haplogroup project. Specifically, it provides STR data on my haplotype (STR signature), which is highlighted in the table, for 111 sampled STR values. My results are grouped with eleven other men based on our similarity in our respective STR haplotype signatures. We also share similarities in SNP tests and have been grouped in the G-BY211678 haplogroup. 

Table Three: 111 STR Results for G-L497 Working Group Members within the G-BY211678 Haplotree Branch 

Source: FTDNA DNA Results for Y-DNA Group Members of Haplogroup L-497 within the FY211678 haplotree branch | Click for Larger View

The table provides the modal haplotype for the twelve individuals (re: third row) and the minimum and maximum values for each of the STRs listed in the table. FTDNA uses the concept of genetic distance (GD) to compare and evaluate genetic resemblance of two or more STR haplotypes. 

It is at this point we start to compare STRs test results among potential test kits to determine if I find any genetic relatives!

What’s Next

Working with Y-STRs and Y-SNPs requires covering the topics of genetic distance,  modal, ancestral haplotypes and the Most Recent Common Ancestor. In the context of these concepts, I will demonstrate the use of some of the Y-SNP & Y-STR Tools listed in Table One.

Sources

Feature Image of the story is a modified version of a featured image from Human Genomic Variation, National Human Genome Research Institute, National Institute of Health (NIH), Page last updated: April 6, 2018, https://www.genome.gov/dna-day/15-ways/human-genomic-variation . It is a visual depiction of comparing SNP mutations between two DNA testers. Aside from the image itself, the article is a good read.

[1] “People usually submit DNA samples in hopes of finding relatives they didn’t know about; just one or two matches might help to complete a family tree or resolve an old debate. However, some men doing Y DNA tests find themselves with an unexpected problem: they’re deluged with dozens to hundreds of “matches” who don’t share a common surname. With further effort they find that these matches are completely unrelated. It appears that somehow all of these men, though unrelated, have converged on a common DNA pattern”

The table below summarizes risk level of convergence. The values are the percent of modern descendants that you would see as matches, using FTDNA’s criterion for the Most Recent Common Ancestor (tMRCA) of less than 21 generations, despite having no family structure other than one founder event.

It is notable that even as recent as 15 generations ago, a high percentage of testers will likely be identified as related because all descendants who share a founder event more recent than 21 generations will be marked as matches. This is frequently seen for emigration-driven founder events such as European emigration to North America and all occurred more recently. While these matches really reflect recent shared ancestry, it makes it difficult to reveal family details.

Rob Spencer, Convergence, Tracking Back: a website for genetic genealogy tools, experimentation, and discussion, no date, page accessed 3 May 2022.

Maurice Gleeson, Convergence – what is it?, 25 May 2017, DNA and Family Tree Research, https://dnaandfamilytreeresearch.blogspot.com/2017/05/convergence-what-is-it.html

Maurice Gleeson, Convergence – quantifying Back & Parallel Mutations (Part 1), 1 June 2017, DNA and Family Tree Research, https://dnaandfamilytreeresearch.blogspot.com/2017/06/convergence-quantifying-back-parallel.html

J David Vance, The Genealogist Guide to Genetic Testing, 2020, Chapter 6

See, Convergence, International Society of Genetic Genealogy Wiki, Page last updated 6 Dec 2018

Rob Spencer has a cogent explanation of convergence: See quote below and reference: Robert W. Spencer , Tracking Back: a website for genetic genealogy tools, experimentation, and discussion, no date, page accessed 3 May 2022.

“The men in question actually are related — this is key — but in a particular way and usually long before the genealogical time span of a couple of hundred years. A group of modern descendants might not care if they have a common ancestor who lived in 1000 AD — but it really matters.”

[2] Y-STR Results Guide, FamilyTree DNA Help Center, https://help.familytreedna.com/hc/en-us/articles/4408063356303-Y-STR-Results-Guide-#panel-4-48-60–0-4

Caleb Davis, Michael Sager, Göran Runfeldt, Elliott Greenspan, Arjan Bormans, Bennett Greenspan, and Connie Bormans, Big Y 700 White paper, March 27, 2019, https://blog.familytreedna.com/wp-content/uploads/2018/06/big_y_700_white_paper_compressed.pdf

Marty Brady, Y Chromosomes and the SNPs STRs, May 16 2020 Presentation, Albuquerque Genealogical Society, Ychromosome_slides.pdf

Ian McDonald, Exploring new Y-DNA Horizons with Big Y-700  19 Oct 2019, presentation was originally given as part of Genetic Genealogy Ireland 2019. https://familytreewebinars.com/webinar/exploring-new-y-dna-horizons-with-big-y-700/]

[3] Y-DNA tools, International Society of Genetic Genealology Wiki, This page was last edited on 30 June 2022,   https://isogg.org/wiki/Y-DNA_tools

Rob Spencer, Deep STR Time, Tracking Back: a website for genetic genealogy tools, experimentation, and discussion, http://scaledinnovation.com/gg/gg.html?rr=deeptime

[4] Rob Spencer, Case Studies in Macro Genealogy, Presentation for the New York Genealogical and Biographical Society, July 2021, Slide 12, http://scaledinnovation.com/gg/ext/NYG&B_webinar.pdf

[5] Rob Spencer, STR Clades, Tracking Back: a website for genetic genealogy tools, experimentation, and discussion, http://scaledinnovation.com/gg/gg.html?rr=strclades

[6] Rob Spencer, Why use STR data and not SNP data?, Tracking Back: a website for genetic genealogy tools, experimentation, and discussion, http://scaledinnovation.com/gg/gg.html?rr=whystr

[7] Introduction to Group Projects, Family Tree DNA Center, https://help.familytreedna.com/hc/en-us/articles/4503173806351-Introduction-to-Group-Projects-

Group Projects, Family Tree DNA Learning Center, https://learn.familytreedna.com/topics/group-projects/

Should I Join A Group Project, Family Tree DNA Blog, Aug 10 2018, https://blog.familytreedna.com/should-i-join-a-group-project/

FamilyTreeDNA Group Projects, Family Tree DNA, https://www.familytreedna.com/group-project-search?browse=true

[8] This example is taken from J David Vance, The Genealogist Guide to Genetic Testing, 2020

[9] SNPs are given names based on an abbreviation that indicates the lab or research team that discovered the SNP and a number that indicates the order in which it was discovered. The prefix, the first letter or group of letters after the main alpha Haplogroup letter identifies the lab or analysis company which first discovered the SNP or was really the first to decide that the mutation at that position on the Y- chromosome was worthy of a name. 

SNPs development indicated by beginning letters:
A = Thomas Krahn, MSc (Dipl.-Ing.), YSEQ.net, Berlin, Germany
ACT = Ancient-Tales Institute of Anthropology, Enlighten BioTech Co., Ltd., Shanghai, China
AD = Dr. Mohammed Al Sharija, Ministry of Education (Kuwait)
AF = Fernando Mendez, Ph.D., University of Arizona, Tucson, Arizona
ALK = Ahmad Al Khuraiji
AM or AMM = Laboratory of Forensic Genetics and Molecular Archaeology, UZ Leuven, Leuven, Belgium
B = Estonian Genome Centre
BY = Big Y testing (next generation sequencing) discovered with the BigY-500, Family Tree DNA, Houston, Texas
BZ = Q-M242 Project, Family Tree DNA, Houston, TX. SNPs named in honor of Barry Zwick.
CTS = Chris Tyler-Smith, Ph.D., The Wellcome Trust Sanger Institute, Hinxton, England
DC = Dál Cais, an Irish group believed to be descended from Cas, b. CE 347, related to SNP R-L226; Dennis Wright
DF = anonymous researcher using publicly available full-genome-sequence data, including 1000 Genomes Project data; named in honor of the DNA-Forums.org genetic genealogy community
E = Bulat Muratov
F = Li Jin, Ph.D., Fudan University, Shanghai, China
F* = Chuan-Chao Wang, Hui Li, Fudan University, Shanghai, China (Beginning letter F; second letter Haplogroup, i.e. FI is Fudan Haplogroup I)
FGC = Full Genomes Corp. of Virginia and Maryland
FT = Big Y testing (next generation sequencing)discovered with the Big Y-700, Family Tree DNA, Houston, Texas
G = Verónica Gomes, IPATIMUP Instituto de Patologia e Imunologia Molecular da Universidade do Porto (Institute of Molecular Pathology and Immunology of the University of Porto)
GG=Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
IMS-JST = Institute of Medical Science-Japan Science and Technology Agency
JD = David Stedman using Big Y and other NGS sources.
JFS = John Sloan
JN = Jakob Nortsedt-Moberg
K = Youngmin JeongAhn, Ph.D; Education: Seoul National University and the University of Arizona
KHS = Functional Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology
KL = Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
KMS = Segdul Kodzhakov; Albert Katchiev; Anatole Klyosov; Astrid Krahn; Thomas Krahn; Bulat Muratov; Chris Morley; Ramil Suyunov; Vadim Sozinov; Pavel Shvarev; SF “National clans DNA project”; EHP “Suyun” Ph.D. of Technical Science; Prof. Elsa Khusnutdinova, Sc.D. of Biological Sciences, Laboratory of Molecular Human Genetics, Institute of Biochemistry and Genetics, Ufa Research Centre, Russian Academy of Sciences
L = Thomas Krahn, MSc (Dipl.-Ing.) formerly of Family Tree DNA’s Genomics Research Center; snps named in honor of the late Leo Little
M = Peter Underhill, Ph.D. of Stanford University
MC = Christopher McCown, University of Florida; Thomas Krahn, MSc (Dipl.-Ing.), YSEQ.net, Berlin, Germany
MF = 23mofang BioTech Co., Ltd., Chengdu, China
MPB = Thomaz Pinotti and Fabrício R. Santos, Laboratório de Biodiversidade e Evolução Molecular (LBEM), Universidade Federal de Minas Gerais, Brazil
MZ = Hamma Bachir, Ph.D., E-M183 Project
N = The Laboratory of Bioinformatics, Institute of Biophysics, Chinese Academy of Sciences, Beijing
NWT = Northwest Territory, Theodore G. Schurr, Ph.D., Laboratory of Molecular Anthropology, University of Pennsylvania, Philadelphia, PA
P = Michael Hammer, Ph.D. of University of Arizona
Page, PAGES or PS = David C. Page, Whitehead Institute for Biomedical Research
PF = Paolo Francalacci, Ph.D., Università di Sassari, Sassari, Italy
PH = Pille Hallast, Ph.D., University of Leicester, Department of Genetics, United Kingdom
PK = Biomedical and Genetic Engineering Laboratories, Islamabad, Pakistan
PLE = Stanislaw Plewako, M. Sci, Baltic Sea DNA Project.
PR = Primate (gorilla and chimpanzee), Thomas Krahn’s WTTY. Some sources have not provided new names when same mutation found independently in humans.
RC = Major Rory Cain, BA(hons), BEd, BSc.
S = James F. Wilson, D.Phil. at Edinburgh University
SA = South America, Theodore G. Schurr, Ph.D., Laboratory of Molecular Anthropology, University of Pennsylvania, Philadelphia, PA
SK = Mark Stoneking, Ph.D., Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
SUR = Southern Ural; SF “National clans DNA project”; B.A. Muratov; EHP “Suyun” Ph.D. of Technical Sciences; Ramil Suyunov; Prof. E.K. Khusnutdinova, Sc.D. of Biological Sciences, Laboratory of Molecular Human Genetics, Institute of Biochemistry and Genetics, Ufa Research Centre Russian Academy of Sciences; Alexander Zolotarev; Igor Rozhanskii; Bayazit Yunusbaev, Institute of Biochemistry and Genetics, Ufa Research Centre, Russian Academy of Sciences
TSC = Gudmundur A. Thorisson and Lincoln D. Stein, The SNP Consortium, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY
U = Lynn M. Sims, University of Central Florida; Dennis Garvey, Ph.D. Gonzaga University; and Jack Ballantyne, Ph.D., University of Central Florida
V = Rosaria Scozzari and Fulvio Cruciani, Dipartimento di Biologia e Biotecnologie “Charles Darwin” , Sapienza Università di Roma, Rome, Italy.
VK = Viacheslav Kudryashov.
VL = Vladimir Volkov, Tomsk University, Russia
Y = Y Full Team (Russian) using data from published and commercial next-generation sequencing samples
YP = SNPs identified by citizen scientists from genetic tests, then submitted to the Y Full team for verification.
YSC = Thomas Krahn, MSc (Dipl.-Ing.) formerly of Family Tree DNA’s Genomics Research Center
Z = Gregory Magoon, Ph.D., Richard Rocca, Vince Tilroe, David F. Reynolds, Bonnie Schrack, Peter M. Op den Velde Boots, Ray H. Banks, Roman Sychev, Victar Mas, Steve Fix, Christian Rottensteiner, Alexander R. Williamson, Ph.D., John Sloan and an anonymous individual, independent researchers of publicly available whole genome sequence datasets, and Thomas Krahn, MSc (Dipl.-Ing.), with support from the genetic genealogy community.
ZP = Peter M. Op den Velde Boots, David Stedman using Big Y and other NGS sources.
ZQ = Gabit Baimbetov, Nurbol Baimukhanov “ShejireDNA project” and other members of the project.
ZS = Gregory Magoon, Ph.D., Aaron Salles Torres from samples from Full Genomes and the Big Y.
ZW = Michael W. Walsh using Big Y.
ZZ = Alex Williamson. Mutations in palindromic regions. Each ZZ prefix represents two possible SNP locations.

Source: Y-DNA Haplogroup Tree 2019-2020, version 15.73, 11 July 2020, Internal Society of Genetic Genealogy, https://isogg.org/tree/

A SNP discovered or identified by YFull starts with a “Y”; a SNP starting with a “BY” or “FT” was named by Family Tree DNA, a “FGC” SNP was named by Full Genomes Corporation, and an “A” SNP was named by YSEQ. An ‘M’ stands for the Human Population Genetics Laboratory at Stanford University.

For specific information on history of the haplotree and related nomenclature, see: International Society of Genetic Genealogy, Y-DNA Haplogrouptree 2019 – 2020, Version: 15.73   Date: 11 July 2020, https://isogg.org/tree/

See also: Y-DNA: FamilySearch, How SNPs Are Added to the Y Haplotree, YouTube Video, Feb 2022, https://www.youtube.com/watch?v=CGQaYcroRwY

[10] Maciamo Hay, Haplogroup G2a, (Y-DNA), Eupedia, Jan 2021, https://www.eupedia.com/europe/Haplogroup_G2a_Y-DNA.shtml

Rootsi, S., Myres, N., Lin, A. et al. Distinguishing the co-ancestries of haplogroup G Y-chromosomes in the populations of Europe and the Caucasus. Eur J Hum Genet 20, 1275–1282 (2012). https://doi.org/10.1038/ejhg.2012.86

[11] Some of the reasons for the differences between the various haplogroup trees are: 

  • Different databases: The databases of the tested men differ between companies and groups. The different databases reflect the SNPs and order of those SNPs that have been found through their analysis of that database. The different companies and analysis groups use different sources for there SNPs: their own testers (YFull does not test), academic databases, historical sources archeological site analysis. 
  • Synomyn SNPs: Different companies may select different synonyms for the same SNP even though  the mutation may appear in same place on each of their Y-DNA haplotrees it may not have the same name. Oftentimes different labs or analysis companies will discover the same SNP and provide independent names for the SNP. Different companies may select different SNPs from the same equivalent block of SNPs that are part of a branch to represent a particular branch of the Y-DNA haplotree.
  • Equivalent SNPS: Each of these haplogroup trees are developed by analyzing a group of tested men and developing a SNP mutation history that shows how these ancestors branched from each other. Many branches have died out before present day men were tested. As more men are tested, mutations will be found that are new but related to specific older branches. If a number of men who are tested by a given company and found to have new mutations they may form a new branch. However, the results from this one company may be viewed by other companies who manage other haplotrees as ‘private’ SNPs and therefore will not be viewed as a new branch. 
  • Selection Criteria: The companies also have different criteria for testing quality, region of the chromosome, for which SNPs belong on their haplogroup tree. SNPs which may be selected by one company may not be acceptable to another.

The three major organizations that manage Y-DNA haplogroups and haplotrees are:

[12] In 2002 the Y Chromosome Consortium (YCC) proposed two widely accepted nomenclature systems for Y-DNA haplogroups: an hierarchical system and a short hand system. Other systems have subsequently been developed and used.

Major haplogroups are labeled with large capital letters (A–T).

  • Hierarchical system:  The hierarchical system is based on characteristics of set theory. The capital letters (A–R) are used to identify the major clades and constitute the front symbols of all subsequent subclades. Subclades nested within each major haplogroup are defined by alternating numbers “1” and “2” and lowercase letters “a” and “b”. An example would be: G2a2b2a1a1b1a1b1a2b.
  • Shorthand – SNP system:  This system is more robust to changes in topology but widespread SNPs have often up to three synonymous names. Additionally different corporations/labs in many cases select an equivalent SNP for the same haplogroup as primary/defining (example G-M201). For seldom and new terminal SNPs there is also the risk that they are not unique (recurrent, unstable) or not detectable with all lab methods.
  • Basic Hierarchy + Shorthand system: since 2013 this system is used by some publications to show the basic hierarchy under a main haplogroup combined with a SNP of a subclade deeper down then the listed hierarchy: example G2a (P15, U5, L31/S149). Especially for unknown SNP names this allows easier recogniation of the basal position.
  • Paragroups are distinguished from haplogroups by using the * (star) symbol, which represents chromosomes belonging to a clade but not its researched subclades defined in the same publication.

Y-DNA project help, International Society of Genetical Genealogy Wiki, This page was last edited on 28 October 2022, https://isogg.org/wiki/Y-DNA_project_help

See also: Y Chromosome Consortium. A nomenclature system for the tree of human Y-chromosomal binary haplogroups. Genome Res. 2002 Feb;12(2):339-48. doi: 10.1101/gr.217602. PMID: 11827954; PMCID: PMC155271. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC155271/

Karafet TM, Mendez FL, Meilerman MB, Underhill PA, Zegura SL, Hammer MF (2008-05). “New binary polymorphisms reshape and increase resolution of the human Y chromosomal haplogroup tree”. Genome Research. doi:10.1101/gr.7172008. Retrieved 2012-04-12

[13] Let’s All Start Using Terminal SNP Labels Instead of Y Haplogroup Subclade Names, Okay? http://www.yourgeneticgenealogist.com/2012/09/lets-all-start-using-terminal-snp.html

Family Tree DNA, Y-DNA: How SNPs Are Added to the Y Haplotree, YouTube Video, Feb 2022, https://www.familysearch.

[14] The FamilyTreeDNA (FTDNA) Time to Most Recent Common Ancestor (TMRCA) estimate (Beta) is calculated based on SNP and STR test results from present-day DNA testers. The uncertainty in the molecular clock and other factors is represented in this probability plot, which shows the statistical probability of the reliability of the birth date in statistical stand deviations, e.g. the most likely time when the common ancestor was born among statistical possibilities.

Click for Larger View.

[15] Rootsi, S., Myres, N., Lin, A. et al. Distinguishing the co-ancestries of haplogroup G Y-chromosomes in the populations of Europe and the Caucasus. Eur J Hum Genet 20, 1275–1282 (2012). https://doi.org/10.1038/ejhg.2012.86

[16a] Big Y Block Tree Introduction, FTDNA Help Center, https://help.familytreedna.com/hc/en-us/articles/4402744197647-Big-Y-Block-Tree-Introduction#accessing-the-block-tree-0-0

[16] See Line 1135 column  S and T in 2019-2020 Haplogroup G TreeY-DNA Haplogroup Tree 2019-2020, International Society of Genetic Genealoloy (ISSOG), Version: 15.73   Date: 11 July 2020 https://docs.google.com/spreadsheets/d/111Iqo0vRt-sr8MJT7pavKQ0qoWxYSc1P7hnMRq3GijU/edit#gid=0

For YFULL SNP designations in their haplotree:

Q: How does YFull determine my Terminal Hg?

A: YFull seeks to place your sample in the YTree as near to the present as is possible by comparing your path of SNP mutations with the paths of SNP mutations of other samples in its database. A “path of mutations” is a list of mutations ranked by the estimated age of each mutation.

If your mutations exactly match those of another sample in the database, your sample will be placed in the same subclade as the other sample and this will be the Terminal Hg (or subclade) of both samples.

In some cases a sample may include an * (asterisk) to indicate that YFull was not able to match the sample with another sample beyond the specified location in the YTree.

At the time you pay your fee to YFull, the location of your sample in the YTree is temporary. When the next version of the YTree is released your Terminal Hg may change. Also, as more samples are added to the YFull database, your Terminal Hg may continue to change.

YFULL FAQ, Last updated on March 28, 2018.  https://www.yfull.com/faq/how-my-sample-located-on-ytree/ also https://www.yfull.com/faq/

[17] Y-DNA project help, International Society of Genetic Genealogy Wiki, This page was last edited on 28 October 2022, https://isogg.org/wiki/Y-DNA_project_help

J David Vance, The Genealogist Guide to Genetic Testing, 2020, Chapter 7

[17a] Rob Spencer, Additional Information for the RootsTech 2022 session “Extending Time Horizons with DNA”, Tracking Back, http://scaledinnovation.com/gg/ext/rt22/info.html?rt

[17b] Rober Spencer, Additional Information for the RootsTech 2022 session “Extending Time Horizons with DNA”, Extinction of Lineages and Surnames, http://scaledinnovation.com/gg/ext/rt22/info.html?rt

[18] The following reflect all of the SNPS associated with the FTDNA G Haplogroup SNPS that I have either tested positive or are presumed positive for the following equivalent variants for each Y-DNA branch. Each SNP mutation represents an individual that is a direct ancestor.

G-M201 root branch: 318 variants

M201, BY21262, BY21263, BY21264, BY2378, CTS10026, CTS1010, CTS1013, CTS10280, CTS1029, CTS10393, CTS10706, CTS10721, CTS10723, CTS10824, CTS10945, CTS11185, CTS11228, CTS11331, CTS1137, CTS1139, CTS11400, CTS11529, CTS11584, CTS11670, CTS11702, CTS11907, CTS11911, CTS12040, CTS12240, CTS12309, CTS1259, CTS12600, CTS12654, CTS1270, CTS12704, CTS12731, CTS1283, CTS12949, CTS13035, CTS1437, CTS1574, CTS1577, CTS1612, CTS1613, CTS1624, CTS1705, CTS1726, CTS175, CTS1750, CTS1768, CTS189, CTS1997, CTS2016, CTS2120, CTS2125, CTS2126, CTS2136, CTS2174, CTS2215, CTS2251, CTS2271, CTS2357, CTS2506, CTS2517, CTS2624, CTS282, CTS34, CTS3693, CTS373, CTS3752, CTS4101, CTS4238, C50S440, CTS4479, CTS4523, CTS4613, CTS4749, CTS4761, CTS4887, CTS5317, CTS5414, CTS5498, CTS5504, CTS5640, CTS5658, CTS5699, CTS5757, CTS5837, CTS6073,CTS635, CTS6483, CTS670, CTS6807, CTS6894, CTS692, CTS6936, CTS6957, CTS7092, CTS7269, CTS7388, CTS7674, CTS7929, CTS8023, CTS827, CTS8531, CTS8717, CTS9011, CTS9190, CTS9593, CTS9641, CTS9707, CTS9710, CTS9894, CTS995, FGC77405, FGC77406, FGC77410, FGC77412, FGC77414, FGC77417, FGC77418, FGC78561, FGC79229, FGC79248, FT32, FT32899, L109, L116, L1258, L1342, L1407, L154, L204, L269, L382, L402, L519, L520, L521, L522, L523, L524, L605, L769, L770, L836, L837, M3438, M3453, M3468, M3489, M3569, M3598, M3601, P257, PF2788, PF2790, PF2791, PF2793, PF2796, PF2802, PF2804, PF2805, PF2806, PF2808, PF2809, PF2815, PF2816, PF2817, PF2819, PF2821, PF2827, PF2831, PF2832, PF2836, PF2837, PF2844, PF2857, PF2858, PF2859, PF2861, PF2862, PF2865, PF2866, PF2867, PF2868, PF2869, PF2871, PF2872, PF2873, PF2874, PF2875, PF2876, PF2877, PF2878, PF2879, PF2880, PF2881, PF2884, PF2888,PF2889, PF2890, PF2894, PF2896, PF2901, PF2902, PF2908, PF2910, PF2914, PF2915, PF2917, PF2918, PF2919, PF2920, PF2921, PF2932, PF2949, PF2954, PF2956, PF2958, PF3022, PF3045, PF3046, PF3048, PF3049, PF3050,PF3052, PF3053, PF3054, PF3057, PF3059, PF3061, PF3063, PF3065, PF3067, PF3068, PF3069, PF3070, PF3071, PF3074, PF3075, PF3076, PF3077, PF3080, PF3083, PF3085, PF3087, PF3088, PF3092, PF3094, PF3103, PF3117, PF3118, PF3121, PF3122, PF3123, PF3134, PF3265, S13661, S13716, S14351, S8863, U17, U2, U20, U21, U3, U33, U7, Y226, Y229, Y231, Y235, Y239, Y245, Y246, Y258, Y271, Y303, Y309, Y332, Y345, Y351, Y375, Y383, Y390, Z3030, Z3067, Z3069, Z3078, Z3080, Z3081, Z3097, Z3104, Z3107, Z3117, Z3135, Z3136, Z3144, Z3145, Z3239, Z3246, Z3247, Z3248, Z3250, Z3262, Z3477, Z3482, Z3485, Z3539, Z6041, Z6116, Z6133, Z6138, Z6324, Z6472

Variants haplogroup G-L89 branch: 32 variants

L89, CTS10089, CTS11196, CTS120, CTS1868, CTS2593, CTS4413, F3198, FGC7254, FGC79817, L142.1, L79.1, M3579, M3614, P287, PF2792, PF2794, PF2795, PF2807, PF2810, PF2830, PF2835, PF2860, PF2864, PF2887, PF2891, PF2895, PF2909, PF3093, PF3119, Z3060, Z3063

Variants haplogroup G-L156 branch: 62 variants

L156, CTS11016, CTS1900, CTS2406, CTS4136, CTS4242, CTS4264, CTS4703, CTS6316, CTS6692, CTS6742, CTS7430, CTS7662, CTS9885, F1239, F1496, F3070, F3220, F3226, FGC37627, FGC77409, L496, PF2785, PF2787, PF2789, PF2797, PF2800, PF2803, PF2814, PF2820, PF2839, PF2840, PF2893, PF2897, PF2898, PF2904, PF2905, PF2912, PF3007, PF3047, PF3091, PF3095, PF3120, PF3125, S13969, V1943, Y125206, Y1415, Y222, Y237, Y238, Y255, Y289, Y321, Y360, Y380, Z3042, Z3056, Z3112, Z3499, Z6105, Z6292

Variants haplogroup G-P15 branch: 57 variants

P15, CTS11463, CTS11627, CTS1879, CTS211, CTS32, CTS5416, CTS5666, CTS6026, CTS6314, CTS6630, CTS6753, CTS8673, CTS9318, F1554, F1975, F1980, F2274, F2301, F2529, F3734, F4086, FGC77420, FGC77421, FGC78558, FGC79059, L149, L31, M3348, M3392, PF2798, PF2799, PF2833, PF2903, PF2911, PF2972, PF2993, PF3034, PF3043, PF3051, PF3056, PF3060, PF3066, PF3073, PF3078, PF3079, PF3082, PF3084, PF3086, U5, Y244, Y251, Y298, Y384, Z3114, Z3506, Z6125

Variants haplogroup G-L1259 branch: 7 variants

L1259, CTS2951, FGC77407, FGC77411, FT81076, PF2824, PF2826

Variants haplogroup G-L30 branch: 47 variants

L30, CTS10449, CTS1093, CTS11324, CTS11434, CTS1180, CTS12810, CTS376, CTS4227, CTS5463, CTS574, CTS7992, CTS90, CTS9763, F1136, F1733, F3139, F788, FGC81433, FGC81737, L1257, L1260, L190, L32, PF2811,  PF2838, PF2870, PF2913, PF3028, PF3089, PF3090, PF3254, PF3270, PF3276, PF3277, PF3278, PF3280, PF3281, Y359, Z3047, Z3051, Z3086, Z3103, Z3238, Z3260, Z3465, Z3487

Variants haplogroup G-L141 branch: 14 Variants 

L141, CTS1891, CTS2488, CTS8143, CTS9605, CTS9957, F2121, FGC81432, PF2813, PF2818, PF3275, Y378, Z3058, Z3074

Variants haplogroup G-P303 branch: 38 variants 

P303, CTS10366, CTS10725, CTS1949, CTS424, CTS4454, CTS6719, CTS688, CTS7698, CTS946, FGC81739, FGC82651, PAGES00098, PF3329, PF3330, PF3332, PF3333, PF3339, PF3342, PF3343, S8782, Y125207, Y253, Y270, Y350, Y354, Y382, Z3481, Z3488, Z3489, Z3490, Z3491, Z3492, Z3493, Z3494, Z3495, Z3496, Z6136

Variants haplogroup G-L140: branch 14 variants

L140, CTS12570, CTS12891, CTS796, PF2823, PF3331, PF3337, Y307, Y324, Z3155, Z3220, Z3245, Z3501, Z767

Variants haplogroup G-PF3346 branch: 1 variant

PF3346

Variants haplogroup G-PF3345 branch: 3 variants

PF3345, FGC799, Z3065

Variants haplogroup G-CTS342 branch: 5 variants

CTS342, CTS2821, Z3039, Z3049, Z723

Variants haplogroup G-L497 branch: 49 variants

L497, BY34319, CTS12867, CTS12895, CTS1899, CTS4197, CTS5351, CTS5762, CTS6235, CTS7111, CTS8596, F3464, FGC470, FGC472, FGC81738, FGC81741, FGC8301, FGC85467, PF6850, PF6852, S10780, Z1822, Z3041, Z3108, Z3147, Z3149, Z3160, Z3169, Z3173, Z3181, Z3207, Z3212, Z3283, Z3390, Z3480, Z3513, Z3528, Z6379, Z730, Z731, Z732, Z733, Z734, Z736, Z737, Z744, Z749, Z750, Z756

Variants haplogroup G-CTS9737 branch: 12 variants

CTS9737, CTS11194, CTS5089, CTS6711, CTS7012, CTS730, Z1900, Z3035, Z3205, Z6380, Z729, Z735

Variants haplogroup G-Z1817 branch: 15 variants

Z1817, CTS11352, CTS11605, CTS3226, CTS8701, FGC475, S25662, Z1821, Z3141, Z3442, Z6900, Z6901, Z742, Z747, Z755

Variants haplogroup G-Z727 branch: 8 variants

Z727, CTS2100, CTS7142, Y3102, Z16776, Z3195, Z725, Z753

Variants haplogroup G-FGC477 branch: 2 variants

FGC477, FGC7516

Variants haplogroup G-Z6748 branch:   29 variants

Z6748, BY8142, FGC476, FGC479, FGC481, FGC482, FGC483, FGC484, FGC485, FGC487, FGC488, FGC490, FGC496, FGC498, FGC499, FGC500, FGC502, FGC504, FGC505, FGC506, FGC507, FGC509, FGC511, FGC512, FGC516, FGC517, FGC518, FT73641, Y172988 

Variants haplogroup G-Y38335 branch: 2 variants

Y38335, Y132516

Variants haplogroup G-FGC486 branch: 5 variants

FGC486, FGC492, FGC494, FGC497, FGC7517

Variants haplogroup G-Z40857 branch: 5 variants

Z40857, FGC510, Y132533, Z40860, Z5838

Variants haplogroup G-Y132505 branch: 2 variants

Y132505, FT47083

Variants haplogroup G-BY211678 brach: 4 variants

BY211678, BY151390, FT47770, Y13253

[19] Andrew Curry, The first Europeans weren’t who you might think, National Geographic, August 2019, https://www.nationalgeographic.com/culture/article/first-europeans-immigrants-genetic-testing-feature

See also:

David Reich, Who We are and How We got Here, Ancient DNA and the New Science of the Human Past, New York: Vintage Books, 2018

Early European Farmers, Wikipedia, This page was last edited on 5 February 2023, https://en.wikipedia.org/wiki/Early_European_Farmers

Reich, David Who We are and how We Got Here: Ancient DNA and the New Science of the Human Past. Oxford University Press. 2018

Lazaridis, Iosif; et al. (July 25, 2016). “Genomic insights into the origin of farming in the ancient Near East”. Nature. Nature Research. 536(7617): 419–424. Bibcode:2016Natur.536..419L. doi:10.1038/nature19310. PMC 5003663. PMID 27459054 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5003663/

González-Fortes, Gloria; et al. (June 19, 2017). “Paleogenomic Evidence for Multi-generational Mixing between Neolithic Farmers and Mesolithic Hunter-Gatherers in the Lower Danube Basin”. Current Biology. Cell Press. 27 (12): 1801–1810. doi:10.1016/j.cub.2017.05.023https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5483232/

Lazaridis, Losif (December 2018). “The evolutionary history of human populations in Europe”. Current Opinion in Genetics & Development. Elsevier. 53: 21–27. arXiv:1805.01579doi:10.1016/j.gde.2018.06.007https://www.sciencedirect.com/science/article/abs/pii/S0959437X18300583

Shennan, Stephen (2018). The First Farmers of Europe: An Evolutionary Perspective. Cambridge World Archaeology. Cambridge University Press. doi:10.1017/9781108386029. ISBN 9781108422925

Nikitin, Alexey G.; et al. (December 20, 2019). “Interactions between earliest Linearbandkeramik farmers and central European hunter gatherers at the dawn of European Neolithization”Scientific Reports. Nature Research. 9 (19544): 19544. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6925266/

[20] Before Present (BP) years, also known as “time before present” or “years before present“, is a time scale used mainly in archaeology, geology and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Because the “present” time changes, standard practice is to use 1 January 1950 as the commencement date (epoch) of the age scale.”

Before Present, Wikipedia, This page was last edited on 29 January 2023, https://en.wikipedia.org/wiki/Before_Present

Regarding the bottleneck, see the following articles:

Karmin, M. et al. A recent bottleneck of Y chromosome diversity coincides with a global change in culture. Genome Res. 25, 459–466 (2015), https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4381518/

Premo, L. S. Hitchhiker’s guide to genetic diversity in socially structured populations. Curr. Zool. 58, 287–297 (2012).

Batini, C. et al. Large-scale recent expansion of European patrilineages shown by population resequencing. Nat. Commun. 6, 7152 (2015).

Poznik, G. D. et al. Punctuated bursts in human male demography inferred from 1,244 worldwide Y-chromosome sequences. Nat. Genet. 48, 593–599 (2016).

[21] Caril Zimmer, In Ancient DNA, Evidence of Plague Much Earlier Than Previously Known, NY Times, Oct 22, 2015, https://www.nytimes.com/2015/10/23/science/in-ancient-dna-evidence-of-plague-much-earlier-than-previously-known.html.

Rasmussen S, Allentoft ME, Nielsen K, Orlando L, et al, Early divergent strains of Yersinia pestis in Eurasia 5,000 years ago. Cell. 2015 Oct 22;163(3):571-82. doi: 10.1016/j.cell.2015.10.009. Epub 2015 Oct 22. PMID: 26496604; PMCID: PMC4644222. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4644222/

Pooja Swali1, Rick Schulting, Alexandre Gilardet, et al, Yersinia pestis genomes reveal plague in Britain 4,000 years ago, January 26, 2022, bioRXiv, https://www.biorxiv.org/content/10.1101/2022.01.26.477195v1.full.pdf

[22] Batini, C., Hallast, P., Zadik, D. et al. Large-scale recent expansion of European patrilineages shown by population resequencing. Nature Communications 6, 7152 (2015). https://doi.org/10.1038/ncomms8152.

Zeng, T.C., Aw, A.J. & Feldman, M.W. Cultural hitchhiking and competition between patrilineal kin groups explain the post-Neolithic Y-chromosome bottleneck. Nature Communications 9, 2077 (2018). https://doi.org/10.1038/s41467-018-04375-6

[23] Zeng, T.C., Aw, A.J. & Feldman, M.W. Cultural hitchhiking and competition between patrilineal kin groups explain the post-Neolithic Y-chromosome bottleneck. Nature Communications 9, 2077 (2018). https://doi.org/10.1038/s41467-018-04375-6

James McNish, The Beaker people: a new population for ancient Britain, Natural History Museum, 22 Feb 2018, https://www.nhm.ac.uk/discover/news/2018/february/the-beaker-people-a-new-population-for-ancient-britain.html

Bell Beaker culture, Wikipedia, This page was last edited on 5 February 2023, https://en.wikipedia.org/wiki/Bell_Beaker_culture

[24] Rob Spencer, SNP Tracker, Tracking Back: A Website for Genetic Genealology Tools, experimentation, and discussion, http://scaledinnovation.com/gg/snpTracker.html

[25] Maps of Neolithic & Bronze Age Migrations Around Europe, Eupedia, https://www.eupedia.com/europe/neolithic_europe_map.shtml

[26] Y-DNA Tools, International Organization of Genetic Genealology Wiki, This page was last edited on 30 June 2022, https://isogg.org/wiki/Y-DNA_tools

[27] Rob Spencer, Introduction to Distance Dendrograms, Tracking Back: A Website for Genetic Genealology Tools, experimentation, and discussion, http://scaledinnovation.com/gg/gg.html?rr=ddintro

[28] Rob Spencer, The Big Picture of Y STR Patterns, The 14th International Conference on Genetic Genealogy, Houston, TX March 22-24, 2019,  http://scaledinnovation.com/gg/ext/RWS-Houston-2019-WideAngleView.pdf Page 11

[29] Rob Spencer, The Big Picture of Y STR Patterns, The 14th International Conference on Genetic Genealogy, Houston, TX March 22-24, 2019,  http://scaledinnovation.com/gg/ext/RWS-Houston-2019-WideAngleView.pdf Page 12

Y-DNA and the Griffis Paternal Line Part Two: Snips and Strings and Other Interesting Things

This is part two of a five part story on utilizing Y-DNA tests to gain knowledge or leads on the patrilineal line of the Griff(is)(es)(ith) family. While I could immediately jump to the results and discuss the Y-chromosomal lineage of the patrilineal Griff(is)(es)(ith) line, I felt it was important to lay the groundwork on the basics of Y-DNA testing and how these results were derived and interpreted.

The growth and advances in genetic ancestry is dynamic and fast moving. It is a field of inquiry that is full of innovations, change and constant discoveries. I imagine this story will be in need of revision within two years based on the rate of technological changes and the updates in the analysis of my original test, and the addition of genetic information from other individuals that are added to the Y-DNA haplotree.

So bear with me while I cover an overview of some of the basic concepts associated with genetic ancestry and a discussion of ‘snips’ (SNPs), ‘strings’ (STRs), haplogroups, haplotrees, and other concepts before delving into the discoveries associated with the Griff(is)(es)(ith) family patrilineal line.

This foray into genetic genealology was personally a circuitous and time consuming process to gain an intuitive understanding of a complex subject. I only hope I have been able to spare the reader from the confusion of what I experienced in making sense of the results of the testing and hopefully provide a clear, direct explanation.

I have oversimplified many of the key concepts associated with genetic ancestry. I still have difficulty comprehending and cogently explaining some of the arcane arguments associated with some of the fundamental concepts and issues in the field of genetic genealogy. From my perspective, some of the concepts underpinning genetic ancestry have not been adequately explained or documented for the layman by the scientific and commercial community. Through my research I have found a number of resources that provide cogent overviews on genetic ancestry. [1] If I have failed to adequately explain some of these subjects, I apologize in advance. If your interest on this subject is piqued, hopefully I have provided footnote references that can lead you to sources that can shed more light on the subject!

The following cartoon captures the attempt to make sense of genetic ancestry and to convey this knowledge to others.

Source: Geneapalooza , 22 Apr 2015.

The desire to discover information on one’s ancestry, the breakthroughs in ancient human genome research, and the technological advances in genetic research have driven the growth of a multibillion-dollar genealogy industry. Genealogy companies have digitalized and have made traditional historical records accessible online. In addition, various types of genealogical DNA tests and services have been expanded and offered to consumers. At the same time, the scientific understanding of the human past is being transformed by innovations in DNA technological testing and statistical breakthroughs and by studies of ancient and modern genetic data.

Both scientists and the wider public are learning more and more about ancestry but the terms that each of these groups utilize are sometimes used in different contexts and have different meanings. With the emergence of genetic or DNA-based genealogical research, it is wise to distinguish the differences between genealogical, genetic and cultural ancestry.

Genealogical, Genetic and Cultural Ancestry

Ian Mathieson and Aylwyn Sacally provide a good distinction between Genealogical, Genetic and Cultural Ancestry:

” … (A)ncestry itself is rarely defined. We argue that this reflects widespread underlying confusion about what it means in different contexts and what genetic data can really tell us. This leads to miscommunication between researchers in different fields, and leaves customers open to spurious claims about consumer genomics products and overinterpretation of individual results. “ [2]

Each of these distinctions are more than conceptual, definitional differences. Each reference a different type of ancestry that are uniquely different from each other and misinterpreting one for the other can lead to false expectations or erroneous conclusions.

Genealogical ancestry probably reflects the most common and intuitive understanding of the term ‘ancestry’. This is similar to what David Vance calls “genealogies’ when discussing research methodologies associated with three levels of genealological research. [3]

Genealogical ancestry is defined in terms of identifiable ancestors in your family tree or pedigree, constructed through family lore and historical documentation. Genealogical ancestry has its limitations because few family researchers are typically able to compile or fortunate to inherit a comprehensive, documented knowledge base of their families beyond 10 generations for which they have tangible records and transcribed family stories.

From a mathematical standpoint, if you search back n generations, you will have minimally 2 n ancestors, not counting siblings, cousins, aunts and uncles. Assuming a generation is about 25 years, for each of us there existed 250 years or 10 generations ago, at the minimum, potentially 210 or 1,024 ancestors for each of us. That is a lot of individuals to conceivably track and have available personal information to construct a family tree and weave family stories.

While many of us may have 1,024 grandparents in 10 generations, the logic that in each generation the potential number of ancestral lines doubles from a pure ‘ancestral’ standpoint utlimately breaks down. [4] This is a perspective based on investigating genealogy from the individual genealogical point of view instead of the genetic point of view. To extend the logic of this argument, in 20 generations, that would make a million possible lines of ancestry; in 40 generations a trillion. A trillion lines of genealogy is impossibly large, larger than the total number of humans that existed.

From a demographic and genetic point of view, these potential lines of descent cannot have been separate; they inevitably converge to a smaller number of actual ancestors. In addition, from a genetic point of view, one has two biological parents and carry two copies of most of one’s genes inherited from each parent. You do not carry four copies from your four grandparents. It is always two autosomal genetic ancestors, no matter how large the genealogy ancestry actually was, until those two ancestors coalesce back into one.

All of us are distant cousins, and so were all of our parents. Each of us is inbred in one sense of the term. It is just that most of us do not know who those shared relatives were. Knowing when this common genetic ancestor lived can reveal not so much about one’s immediate family, but about how the population evolved. A geneticist can extend the same idea to more and more people, taking their shared genetic ancestors step by step, to trace the most recent common ancestor, or tMRCA, of all the copies of the gene. This leads us to genetic ancestry.

Genetic ancestry refers to people who have contributed to the composition of one’s genome. [5] The genome is the full set of genetic code each of us inherits from our parents and ancestors. Genetic ancestry refers not to your pedigree but to the subset of paths through it by which the material in your genome has been inherited.

One’s genetic ancestry consists of a small part of one’s genealogical ancestry. The genetic impact diminishes after the 4th or 5th past generation. For example, full siblings have identical genealogical ancestors but differ in their autosomal genetic ancestry because they inherit different chromosomal segments from their parents. For two siblings the average have 50 percent of the same DNA. [6]

The illustration below shows the average amount of autosomal DNA inherited by all close relations up to the third cousin level. The illustration uses the maternal side as a an example. The percentages can be replicated for the paternal side. [7]

Illustration 1: Autosomal Genetic Inheritance from Descendants

Source: courtesy Dimario, Wikimedia Commons. Click for larger view.

Autosomal DNA is inherited equally from both parents. The amount of autosomal DNA inherited from more distant ancestors is randomly shuffled up in a process called recombination and the percentage of autosomal DNA coming from each ancestor is diluted with each new generation.

For males, Y-DNA is inherited directly from the father and his direct male descendants through the Y chromosome. For females, X-DNA is inherited from both the father and mother. For all individuals, mitochondrial DNA is inherited directly from the mother and her direct female descents.

Another way of looking at the diminished impact of autosomal genetic inheritance through prior generations is viewing the entire genome of an individual. As indicated in illustration 2, the number of ancestors one has doubles every generation. However, the number of stretches (lengths of DNA that ancestors have contributed to you) increases by only around seventy-one per generation [8]. Going back eight or more generations it is almost certain that one will have some ancestors whose DNA did not get passed down. If one goes back fifteen or more generations, the probability that one ancestor contributed DNA directly is exceedingly small.

Illustration 2: Genomic Genetic Influence

Source David Reich, Who We are and How We got Here, Ancient DNA and the New Science of the Human Past, New York: Vintage Books, 2018, page 12. Click for larger view.

Genetic genealogy or results from ancestry DNA tests do not tell you where each member on your family tree lived or their origins. Depending on the DNA test, they instead tell you how much of their DNA you have inherited from unspecified ancestors on each side of your family or through a maternal or paternal line.

Traditional genealogical research constructs family trees of individuals, exhibiting links , facts, and relationships between relatives. Genetic ancestry compares individual genomes, haplotypes, or sampled areas of chromosomes with other targeted individuals or with an average genome of a population reference sample. When geneticists and consumer DNA ancestry companies talk about genetic ancestry they are really talking about genetic similarity between populations and individuals, genetic distance, and most recent common ancestor [9]

Genetic Distance

The number of differences or mutations between two sets of Y-chromosome DNA or mitochondrial DNA test results. A genetic distance of zero means that there are no differences in the two results and there is an exact match. For autosomal DNA comparisons genetic distance relates to the size of a shared DNA segment. The genetic distance is then the length of the segment in centiMorgans. [9]

Haplotype

A modal haplotype is the most commonly occurring haplotype (a set of STR marker values) derived from the DNA test results of a specific group of people. The modal haplotype does not necessarily correspond with the ancestral haplotype – the haplotype of the most recent common ancestor. [9]

The ancestral haplotype is the haplotype of a most recent common ancestor deduced by comparing descendants’ haplotypes and eliminating mutations. A minimum of three lines, as distantly related as possible, is recommended for deducing the ancestral haplotype. This process is known as triangulation. [9]

the Most Recent Common Ancestor

In genetic genealogy, the most recent common ancestor (tMRCA) of any set of individuals is the most recent individual from which all the people in the genetic group are directly descended.[9]

Genealogical data can be represented in several formats, for example, as a pedigree or ancestry chart. Family trees are often presented with the oldest generations at the top of the tree and the younger generations at the bottom. An ancestry chart, which is a tree showing the ancestors of an individual and not all members of a family, will more closely resemble a tree in shape, being wider at the top than at the bottom.

Illustration 3: Example of Ancestry Chart

Example of a genealogical ancestry chart. Click for larger view.

In a pedigree chart, an individual appears on the left and his or her ancestors appear to the right. Conversely, a descendant chart, which depicts all the descendants of an individual, will be narrowest at the top.

Illustration 4: Example of Pedigree Chart

Example of a pedigree chart, click for larger view.

In genetic genealogy, the changes or mutations in individual genomes are represented in phylogenetic haplogroup trees and in STR Distance Dendrograms.

Illustration 5: Portrayal of Different Genealogical information : Phylogenetic Haplogroup Trees, Family Trees and Genetic Distance Dendrograms [10]

Source: Understanding DNA, Family Tree DNA
Click for larger view.
The STR Dendrogram is a diagram similar to a family tree. Individual DNA testers are the dots at the right. Time moves backward to the left. On a traditional family tree, branch points are ancestors. In the dendrogram the branch points are generally not specific people but points in time when genetic changes occurred. 
Click for larger, legible view.

Cultural ancestry is another category of how we define genealogy. It is based on whether someone is embedded in or exhibit the cultural traditions of a particular social group that may be based on a specific geographical area. It is oftentimes associated with ethnic and racial connotations or groups.

An intuitive example of the interplay between genealogical, genetic, and cultural ancestry is determining the tribal identity of an individual with a single Native American grandparent. This person may have not inherited any native American chromosome segments, their autosomal genetic ancestry would reflect zero percent Native American. However, if they were brought up in a Native American tribe, their cultural ancestry and way of living may exhibit native American customs. Finally, their genealogical ancestry would reflect that they are 1/4 Indian since they had one grandparent that was of Indian descent. Depending on the Native American tribe, there are different requirements based on genealogical ancestry to be recognized as part of the tribe. For example, the Eastern Band of Cherokee Indians require a minimum of 1/16 degree of Cherokee Indian blood for tribal enrollment, while the Bureau of Indian Affairs’ Higher Education Grant expects you to have the minimum of 1/4 Native American blood percentages. [11]

Another example of how cultural ancestry has been interpreted (or misinterpreted) is a humorous popular commercial from ancestry.com that illustrates the practical interplay and distinction of genealogical ancestry, genetic ancestry and cultural ancestry.

The use of cultural genealogy is often mistakenly used in the context of interpreting the results from traditional genetic genealogy tests. DNA is not the same as cultural heritage. Marketing tactics of various consumer based genealogy tests tend to play up the link between ethnic heritage or cultural ancestry and genetic genealogy [12]

The tendency to attribute cultural relationships with genetic results is also found when discussing what David Vance calls ‘deep ancestry’ or ‘lineages’. We need to be careful in a similar fashion not to associate deep ancestry haplogroups or lineages with historical cultures and, in turn, associating historical cultures with our personal ancestors. At this level, we rely more on archaeology and anthropology to describe groups of ancestors at the deep ancestry level.

Blending the three views of genealology

Scientific and scholarly advances in archaeology, linguistics, genomics, and ancient anthropology have revolutionized our understanding of history and prehistory . The study of the ancient human past is blurring the lines between humanities and science. Ancient genomics or paleo genomics, ‘deep ancestry’, can provide one but only a partial descriptive aspect of this study. It is apparent that that the reconstruction of ancient human migrations and their social characteristics is a complex subject that will continue to gain benefits from a multidisciplinary approach of study. Revelations in this multidisciplinary area will certainly add historical context to understanding genealogical ancestry. [13]

Various theories have been formed that describe large cultural groups and major population movements where most of the members of a genetic haplogroup may have lived and traveled. Common ancestors with matches from these time periods can be mapped and described but any information about where these ancestors lived and migrated is gained from studies that are not connected to our personal history. There is no direct evidence that our individual ancestors were part of the same culture or migration patterns that are documented in paleogenomics. We can not definitively associate deep ancestry haplogroups with historical cultures. However, the results of these multidisciplinary studies can provide a backdrop for interpreting or providing meaning and context to a haplogroup tree.

Analyzing DNA from present-day testers and ancient genomes provides a complementary approach for dating evolutionary events and migratory patterns. Certain genetic changes occur at a steady rate per generation. They provide an estimate of the time elapsed. These changes accrue like the ticks on a stopwatch, providing a “molecular clock.” By comparing DNA sequences, geneticists can not only reconstruct relationships between different populations or species but also infer evolutionary history over deep timescales.

“Molecular clocks” are based on two key biological processes that are the source of all genetic variation: mutation and recombination. [14]

Mutations are changes to the letters of DNA’s genetic code. DNA mutations can be used to estimate the timing of branches in our evolutionary tree. They compare the DNA sequences of two individuals or species, counting the neutral differences that do not alter one’s chances of survival and reproduction. The time needed to accumulate the differences can be calculated based on the knowledge of the rate of changes in the mutations. . This will indicate how long it has been since someone shared genetic ancestors from a common ancestor.

Recombination is the other major way DNA accumulates changes over time. It leads to the shuffling of the two copies of the genome from each parent which are bundled into chromosomes and mitochondria. The child’s genome is a mosaic of your parents’ DNA.

Genetic changes from mutation and recombination provide two distinct clocks, each suited for dating different evolutionary events and timescales. Because mutations accumulate so slowly, this clock works better for very ancient events, like evolutionary splits between species. The recombination clock, on the other hand, ticks at a rate appropriate for dates within the last 100,000 years.

Overview of DNA and Type of Genetic Genealogy Tests

There are, as reflected in illustration 6, essentially three sources of DNA for genetic testing:

  • All 23 chromosomes (autosomal and sex chromosomes);
  • Y Chromosome; and
  • Mitochondrial DNA

Illustration 6: Location of DNA in Human Cell

Source: FamilyTreeDNA [15]

As indicated in Table One, while limited to the paternal line of descent, Y-DNA tests can effectively track male genetic descendants back 300,000 years. Mitochondria testing of the matrilineal line can also provide results that go back over 140 thousands of years. The popular ‘ethnicity’ tests, as previously indicated, can trace back through a limited number of generations. While women have two X chromosomes, DNA testing of the X-DNA is usually tested along with other chromosomes as part of an atDNA test. [16]

Table 1: Type of DNA Testing

CharacteristicAutosomal
DNA
Y – DNAMitochondrial
DNA
What does it test?All 23 chromosomesY chromosomeMitochondria
How far back?5 – 9 generations300,000 + years140,000+ years
What genealogical lines?All ancestry linesPaternalMaternal
Available from:– ancestry.com
– Family Tree DNA
– 23andMe
– Myheritage
– Living DNA
– Family Tree DNA
– 23andME (high level)
– YSEQ
– Full Genome Corp
– Family Tree DNA
– 23andMe
– YSEQ
– Full Genome Corp

The human cell is a masterpiece of data compression. [17] Its nucleus, just a few microns wide, contains (if you spell it out) six feet of genetic code comprised in a double helix called the DNA: deoxyribonucleic acid. (See illustration 7) The DNA helical molecules string together some three billion pairs of nucleotides that are comprised of proteins, sugar (deoxyribose), a phosphate and four types of nitrogenous bases which are represented by an initial: A (adenine), C (cytosine), G (guanine), and T (thymine).

The nucleotides or base pairs are the cornerstone of genetic testing. They are the foundation of the programming language of our genetic code. Whenever a particular base is present on one side of a strand of the DNA, its complementary base is found on the other side. Guanine always pairs with cytosine and thymine always pairs with adenine. So we can write the DNA sequence by listing the bases along either one of the two sides or strands. When DNA companies perform their tests, they essentially separate the two stands of the helix and use one side of the helix as the template or coding strand when they map out an individual’s DNA results.

Illustration 7: Structure of Deoxyribonucleaic Acid

Source: Ruairo J Mackenie, DNA vs. RNA – 5 Key Differences and Comparison, 18 Dec 2022, updated 31 Mar 2022, Technology Networks, Genomics Research, https://www.technologynetworks.com/genomics/lists/what-are-the-key-differences-between-dna-and-rna-296719

If bases are like the letters of your genetic story, individual genes can be thought of as paragraphs or strings of these bases, and chromosomes can be thought of as chapters of a book. In total, humans have about 20,000 genes located on 23 pairs of chromosomes.

In keeping with the book analogy, an human’s whole story is actually like receiving 2 different editions of a 23-chapter instruction manual, one from both parents. Within each set of chromosomes, one is a sex chromosome responsible for determining sex characteristics, while 22 are autosomes which provide information for everything else. In humans, there are 2 different types of sex chromosomes; the X chromosome or the Y chromosome. Mothers always pass along one copy of an X, while fathers can pass along either another copy of X to create a female or a copy of Y to create a male.

What we call a gene is actually tiny fragments of these base chains that typically contain around 1,000 unique sequences of the bases which are used a templates to assemble the proteins that do most of the work in our cells. In between the genes is the noncoding “junk” DNA. [18] Together, these chromosomes contain all of the information needed to build a human being.

It is mind boggling to comprehend that the a human genome is made of 3,200 million base pairs, split into these 46 chromosomes. What is equally amazing is an human genome is 98% identical to a chimpanzee’s genome, and 97% to a gorilla’s. Gorillas are in fact 97% identical to either humans or chimps, meaning that humans are more chimp-like than gorillas. In comparison, two random human beings are on average 99.5% identical. [19]

Illustration 8: Human Cell, Chromosome, DNA and Genes

Diagram of chromosome and DNA structure. Click for larger view.

These DNA strands are divided into coiled chromosomes. Two of them—labelled either X or Y—determine our biological sex. The remaining twenty-two pairs, known as autosomal DNA, are encoded with information about our traits: bone structure, eye color, skin color, the stuff of being human.

Approximately 2% of our genome encodes proteins – this is where gene strands are located (illustration 7). Genes are the basic unit of inherited DNA and carry information for making proteins, which perform important functions in your body. The remainder of our genome is made of noncoding DNA, sometimes called “junk DNA”, which is a misnomer. It is estimated that between 25% and 80% of non-coding DNA regulates gene expression (e.g. when, where, and for how long a gene is turned on to make a protein).

Illustration 9: Coding and Noncoding DNA

Source: Ancestry,com | Click for larger view.

One way to think about this is to resort to the book analogy again, imagine your DNA as cookbook paragraphs with recipes for making proteins. The paragraphs with the list of ingredients and measurements are your genes—there are only a few of these pages in the cookbook. The other paragraphs are the recipe instructions, telling you how and in what order to do things. The non-coding DNA that does not regulate gene activity is composed either of deactivated genes that were once useful for our non-human ancestors (like a tail) or parasitic DNA from virus that have entered our genome and replicated themselves hundreds or thousands of times over the generations, or generally serve no purpose in the host organism. [20]

The order of the base letters can be read by DNA sequence machines that perform chemical reactions on fragments of DNA, releasing flashes of light as the reactions pass along the length of the DNA sequence. The reactions emit a different color of each of the bases so that the sequence of letters can be scanned into a computer by a camera. Illustration 8 is an example of a photograph of all of the chromosomes.

Illustration 10: Karyogram of Human Chromosomes

The image, a karyogram, is a photograph of the human cartogram which is all of the chromosomes of the human cell arranged in pairs in a numbered sequence from longest to shortest. To make a karyogram, researchers stain chromosomes with a special chemical and then take a photograph of the stained chromosome.  The chromosomes are then digitally rearranged and organized into  a specific numbered sequence.  This karyogram also includes a ring of mtDNA for reference. [21]
Click for larger view.

The following illustration 11 provides an ideogram of all of the human chromosomes. Basically an ideogram provides a schematic diagram of a chromosome that shows the mapping or location of genes as bands. I have provided this illustration as a precursor to discussing the location of genetic markers on the Y-DNA chromosome that are used for Y-DNA testing.

Illustration 11: Idiogram of Human Chromosomes

An idiogram of the human chromosomes. An ideogram is a schematic diagram of a karyotype. An Idiogram shows the chromosome maps indicating the locations of genes as bands. It is not an actual picture of total chromosomes of a cell. However, an ideogram provides much information about each chromosome. Most importantly, it provides locations of individual genes present in a chromosome. [21] .
Click for larger view

Since humans share roughly 99 and a half percent of the same chromosomes, mutations with that half percent are the source of ‘genealogical’ variations among humans.  It is in those regions of the DNA that are variable where genetic ancestry distinctions are found. DNA polymorphisms (letter changes in the nucleotides) are currently the choice markers in DNA ancestry testing. The concept of ancestry markers, referred to as ancestry information markers (AIMs) has been documented and validated in numerous studies.

Ancestry information markers refers to locations in the genome that have varied sequences at that location and the relative abundance of those markers differs based on the continent from which individuals can trace their ancestry. So by using a series of these ancestry information markers, sometimes 20 or 30 more, and genotyping an individual you can determine from the frequency of those markers where their great, great, great, great ancestors may have come from. [22]

When analyzing DNA for genealogical purposes it was found that that there are specific regions in the DNA that provide reliable, efficient areas to identify these differences. These regions are analyzed in detail and look at representative sections called markers, distributed across a large region of a chromosome. Each marker has specific variations (or values) called alleles .  Each marker has also been found to change at different rates of mutation. Looking at allele variations among a wide set of markers has been found to be an effective approach to studying differences between groups of genomes (individuals) and identifying a unique genome (haplotype) .  Each of us have an unique haplotype based on specific DNA markers.

The DNA testing methods used by the majority of scientific research and genetic DNA companies focus on evaluating the differences of values (alleles) in specific base sequences contained in the DNA strands. These differences are due to random errors (mutations) in copying genomes. It is these differences, incurring about every thousand letters in both genes and junk DNA that geneticists study to learn about past generations and how similar we are to others that have completed similar tests.. Over the three billion letters in the genome there are around three million differences separating two genomes.

The type of testing technology used by Family Tree DNA, 23andMe, Ancestry.com, and similar companies test less than 0.1 percent of your genome. Their tests, which are called genotyping microarray tests, do not sequence your genes and do not test your whole genome.  Although the sequencing of an entire genome currently costs less than $1000, the analysis, interpretation and counseling brings the cost to $3000 (though in the case of cancer treatment the cost will be $10,000).  [23] If humans differ by 0.1 percent of the genome, then only 15 percent of that 0.1 percent can explain a lot in terms of population differences. [24]

As DNA is copied and passed passed down through successive generations it gradually accumulates more mutations.  People more closely related to each other have fewer differences in the sampled DNA markers. The more distantly related one is from another relative, more differences or mutations can occur. 

At its most simplest level of explanation, genetic DNA testing is based on an analysis of a specific, targeted sampling of these nucleotide locations on a DNA strand in a chromosome or mitochondia. The specific values exhibited at the these targeted locations are then utilized to identify the tester’s haplogroup and locate the results on a branch of the Y-DNA haplotree. The results are also used to determine the similarity of the results with other individual samples.

The higher the density of differences separating two genomes on any segment, the longer it has been since the segments shared a common ancestor as the mutations accumulate at a more or less constant rate over time. The density of differences provides a biological stopwatch, a record of how long it has been since key events occurred in the past. [25]

The Basis of Y-DNA Testing: “Snips” (SNPs) and “Strings” (STRs)

It has been determined that the Y chromosome is 57,227,415 base pairs in length. Not all these base pairs are suitable for genetic analysis. The two tips of the chromosome are called telomeres and are known as pseudoausomal (PAR) regions (PAR1 is 2.7 million base pairs in length and PAR2 is 0.34 million base pairs in length). The PAR areas are not utilized for genetic testing since they do not have stable regions to trace Y-DNA markers. These two end areas can recombine with the X chromosome, this is why these areas are referred to as “pseudo autosomal” regions. [26]

There are other areas of the Y chromosome that are not ideal for genetic testing. These hard to read areas are made up of regions of highly repetitive base pairs that are not suitable for the ‘short read’ DNA testing technology that companies typically use. While Family Tree DNA has been successful in reading some of the difficult to read areas using their third generation sequencing techniques associated with their Big Y 700 test, the bulk of these areas are not considered useful for current genetic genealogy (areas generally depicted in the right hand shaded area in illustration 12). Subtracting those hard to read regions of the Y Chromosome, one is left with about 40 percent or 57.2 million base pairs on the Y chromosome. [27]

Illustration 12: Base Pair Numbering of the Y Chromosome

Source: J David Vance, The Genealogist Guide to Genetic Testing, 2020, Chapter 13. Click for larger view.

There are basically two major types of mutations on the Y chromosome that are analyzed and used to identify Y-DNA haplogroup affiliation, haplotypes, and estimating genetic distance through a variety of DNA tests in genetic ancestry.

Single Nucleotide Polymorphisms – SNPs

“Snips”

Single nucleotide polymorphisms, frequently called SNPs (pronounced “snips”), are the most basic type of genetic variation. SNPs center on mutations associated with a single base letter or nucleotide position in the DNA strand on the Y chromosome. For example, a SNP may replace the nucleotide cytosine (C) with the nucleotide thymine (T) in a certain stretch of DNA. [28]

A SNP is a difference of a single nucleotide between two males which identifies a mutation. If only one descendant exhibits the mutation, the SNP would appear to be a private variant (a term used by Family Tree DNA) or an novel SNP (a term used by YFull) of the SNP for the individual. Once two or more descendants test and are identified as sharing the mutation, the variant would be given a name by the testing company or lab.  It may possibly have several synonym names given by several labs.  [29]

Essentially, a male in whom a SNP mutation first appears passes it on to his sons and all their male descendants which could be hundreds or several thousand years. Over time specific other SNPs change, but the earlier changes in the other SNPs are still preserved through the generations. Y-DNA therefore contains a cumulative record of all of the SNP mutations that have ever occurred in a man’s paternal line.

SNPs are a genetic source to document genetic ancestry and the Y-DNA haplotree. Based on the tracking of the various SNP mutations, SNPs provide reliable information on one’s position in the Y chromosome haplotree and haplogroups – providing information on deep ancestry. Each branch in the Y-DNA haplotree represents an individual who had an unique SNP mutation and passed that mutation on to subsequent male descendants.

Short Tandem Repeats – STRs

“Strings”

The second type of mutation focuses on variations of repeated patterns of two or more nucleotide sequences at designated positions on the Y chromosome. Short-tandem repeats (STR’s), pronounced as ‘strings’, are also known as microsatellites. STR’s occur at specific locations on the Y-chromosome, which are often referred to as loci. [30]

“STRs are analogous to a genetic stutter, or the copy machine getting stuck. ” [31]

These repeated patterns vary in the length and number of repeats. For example the STR marker named DYS393 has a repeat motif of base nucleotides AGAT with a repeat (allele) range of 9-17. [32] So the allele value for the following repeat pattern for the DYS393 marker would be 9:

The number of repeats that a specific person has in a STR typically gets passed down to their sons unchanged. However, sometimes a copy error occurs and a repeat is gained or lost.

By themselves, Y-chromosome DNA (Y-DNA) short tandem repeat (STR) markers from a Y-DNA test do not have any particular meaning. The value of testing Y-DNA STR markers comes from creating a Y-DNA signature (haplotype) and comparing that Y-DNA signature to other testers in a database.

A Y-DNA STR signature or haplotype will comprise the allele values for a set of 12, 25, 37, 67, or 111 STRs (depending on the test). The more STRs that are part of the comparative signature, the ‘more reliable’ the results when comparing other testors’ results. They are useful for genetic genealogy because an individual’s Y-DNA signature distinguishes their paternal lineage from others. They can then be used with a company’s comparative database to discover genealogical connections or historic ancestry. Oftentimes, specific allele values for specific STRs are also associated with specific haplogroup subclades.

By comparing more markers, we are able to get a clearer idea or more reliable estimate of the degree of similarity between two or more Y-STR signatures. The more differences there are in the markers, the more generations have passed since the paternal line split for the two individuals. If you think of the matching database as a puzzle consisting of 111 pieces, the more pieces you compare means the more complete the picture becomes. 

Because there are many more places within an STR than an SNP for a copy error to occur, STRs have a faster mutation rate than SNPs. Unlike SNPs, STRs rarely go more than a few hundred years without a change. 

Depending on specific STRs, the mutation rates can vary. The results of these mutations largely provide information on matching other testers at what we have referred to as the “deep lineage perspective”. [33]

More on Snips (SNPs)

There are roughly 15 million SNPs in a person’s genome. To be technically classified as a SNP, a variant is found in at least 1 percent of the population. This definition of a SNP is a bit circular since it would be difficult to state with certainty that a given SNP represents one percent of the population. [34]

Any of the positions in the Y-DNA are potential candidates for a mutation of various types. Any change in a specific base letter can be considered a SNP.  However, technically the type of mutation, from a genetic standpoint of interest, is what is called a Unique Event Polymporhism (UEP). UEPs are basically rare mutations that occur so infrequently that they are considered to all come from a single, common ancestor. The EUP markers were used to establish the haplotree and are continued to be used to establish new ‘branches’ or subclades in the haplotree. The EUP is the central tenet on which the Y-DNA haplotree and the genealogical analysis of deep ancestry branching, using SNPs, is based. [35]

The properties of UEPs can be contrasted with those of short tandem repeat sequences (STRs). Unlike UEPs, STR sequences are highly variable, and there is a significant probability that one of a set may have changed its repeat number after only a few generations. That makes a particular STR haplotype much more specific, matching a much smaller number of people. But it also means, at least in the case of Y-STR markers, that quite unrelated lineages may have converged to the same combination of Y-STR markers entirely independently by different routes. This is known as convergence. Without knowledge of one’s major Y-DNA Haplogroup or branch (subclade), one can erroneously conclude that two similar haplotypes are genetically related. [36]

There are a few exceptional cases where Y-STR markers can take on the status of UEPs, typically where a large-scale deletion event may have occurred, causing a sudden big change in the Y-STR repeat number rather than the usual single increment or decrement, which can be considered to have been a unique one-off in a group of lineages. Such a change in the STR marker DYS 413 for example distinguishes subgroup J2a1 from J2a in Y-DNA Haplogroup J. [37]

The relative mutation rate for an SNP is extremely low. This makes them ideal for documenting or marking and tracing the history of genetic mutations in the human genetic tree (haplotree) over long periods of time. Many generations can pass without a SNP occurring. This means that SNPs that occur in a specific lineage are unique and seldom change back. They occur thousands or tens of thousands of years ago. Some are more recent, and as science evolves as well as the increase of commercial DNA testers increases, more EUPs are being discovered in just the past few generations. [38]

Presently, Family Tree DNA has identified over 200,000 markers or SNPs on their public Y-DNA haplotree. The illustration below reflects where those SNP markers are on the Y chromosome. This does not represent all the SNPs discovered by the company but the ones that have been mapped on their public haplotree. [39]

Illustration 13: Region on Y Chromosome Where SNPs have been Mapped

Source: J David Lance, The Genealogist Guide to Genetic Testing, 2020, Chapter 15 Click for larger view.

The labeling system for SNPs is not intuitive. SNPs are technically identified based on a Reference SNP Cluster Id (RSID). The specific identification is assigned and documented in the National Center for Biotechnology Information (NCBI) dbSNP database.  Whether or not a SNP is given a name, it has a documented position on the Y chromosome and a mutation description.  A SNP will sometimes be referred to based on its position in a format like ‘12345678-A-G’ which means that the SNP as a mutation from the A to G base at position 12345678 on the Y-chromosome. 

The general format for a SNP name will include an alpha prefix and a number suffix. The alpha prefix identifies the lab or analysis company which first discovered the SNP or was the first to decide that the mutation at that position on the Y- chromosome was worthy of a name.  The letters are followed by a series of numbers which are an unique number assigned by the laboratory or company which named the SNP. The names of SNPs have no relationship to its position on the Y Haplogroup tree. The names are completely assigned independently on how old the SNP might be, an artifact of timing and discovery. [40]

More on Strings (STRs)

Y-chromosome STRs have demonstrated their value in the forensic identification of male Y-DNA from sexual assault cases, tracing paternal lineages to aid in missing persons investigations, historical studies and to help linking families through genetic genealogy. Forensic Labs usually use PowerPlex Y (Promega Corporation) and Yfiler (Applied Biosystems) kits that examine 12 or 17 Y-STRs, respectively. [41]   Genealogical DNA test labs currently examine over 700 Y-STRs. and provide a range of different Y STR tests depending on the number of STRs tested. [42]

DNA testing companies or labs in certain cases use different nomenclatures to designate the same Y-STR allele. A conversion must be applied in these cases to accurately compare Y-STR results obtained from different companies. The most common nomenclature is based on guidance provided by NIST for Y-STR markers historically reported differently by various companies. The NIST standard is the proposal of ISOGG (International Society of Genetic Genealogy) for genetic genealogy companies.

In the year 2000 when the field of genetic genealogy was emerging, there were only about 20 Y-STR markers known to exist on the Y-chromosome. [43] Around 2008, there were about 400 STRs identified on the Y chromosome, many of which were not useful for forensic or genetic research. The various companies that provided Y-STR results to the genetic genealogy community at that time used about 120 different loci or STRs. However, many of STRs overlapped between test providers and the various allele values similar STRs were different between companies and organizations. [44]

Over time, a number of STRs located at specific areas of the Y-chromosome were consistently collected and compared. These STRs currently represent the most consistently studied set of mutations used for analyzing data across all men who have tested their Y-DNA. These markers were originally selected based on their ability to be reliably reported and had a mix of mutation rates (slow to fast) that could effectively discriminate differences between individual tests. [45] Presently, over 28,000 STRs in the Y-DNA have been identified and most have yet to be identified. [46]

Testing additional STR markers can also help refine the matches and refine DNA results for the individual placement on the Y-DNA haplotree. Testing more than the traditional 111 STR markers means that the information is more relevant to your personal ancestry related to the deeper origins of one’s genetic personal history (historical and anthropological). The Big Y-700 SNP test provides these type of results. There were at least 500 STRs in the Big Y-500 test and there are at least 700 STRs in the Big Y-700 test (111 + 589), however, the additional 589 are currently extraneous information for STR based testing as the matching system for those STRs is not yet fully developed. [47]

All STRs are given a unique identification number. The format usually includes a three alpha prefix and then a number. For example, for the STR named DYS393: the D indicates that the segment is a DNA segment, the Y indicates that the segment is on the Y chromosome, the S indicates that it is a unique segment, and the number 393 is the identifier. [48]

For purposes of genetic genealogy, over the course of the past 20 years, 111 of the STRs have been identified, named, and have been used for Y-DNA research.  These markers were originally selected  based on their ability to be reliably reported and had a mix of mutation rates (slow to fast) that could effectively discriminate and differentiate differences between individual testers. 

STRs may change by adding or subtracting a repeat or two during the replication process. Estimates of the frequency of changes range from less than 2 mutations per 1000 generations to over 7 per 1000 generations for each STR, depending on which marker. Over a long period of time, individuals will tend to have at least some differences in the values (number of repeats) on the various STR markers on their Y-chromosome. If you look at 25 markers, there is about a 50% chance you will find at least one mutation in 9-10 generations (or, counting both up and down from a common ancestor, between yourself and a 4th cousin). For example, STR marker DYS391 can have allele values ranging from 7 to 14 repeats, with 10 and 11 being common in populations with European ancestry. [49]

Illustration 13: Idiogram of Y Chromosome Showing Location of the First 111 STR Markers for Y-DNA Test

Locations on the YDNA chromosome for the first 111 STR markers from Family Tree DNA [50]

The 111 STRs are usually broken into four subgroups based on testing options that make up the bulk of the matching databases: 12, 27, 64, and 111 markers. Based on studies, the first 12 markers are by comparison relatively slow having an average mutation rate of around one mutation every 16,000 years. The first 37 markers are the most volatile markers 13-37, having an average mutation rate every 7,700 years.  The next 67 markers (37-67 including the prior markers) have an average rate of 11,000 years.  The full set of 111 markers have an average mutation rate of 11,000 years. [50]

The following three charts list all of the STR markers that are used in the standard Y-111 STR test with the mutation rates.

Illustration 14: Mutation Rates of the 111 STR Markers Used in FTDNA STR Tests [51]

The following chart (Illustration 15) represents the results of my Y-DNA STR 111 test from FTDNA. The number below each STR marker number indicates the allele value , i.e., the number of times a particular sequence of alleles repeats itself in a specific location on the Y chromosome. The combined values for these markers is my Y-DNA signature (haplotype). It can be used to compare my results with other Y-DNA testers.

Illustration 15: Y-DNA STR Values (Haplotype) for the Y-111 STR Test for James Griffis

Results for the FamilyTree DNA Y-111 STR test. | Click for larger view.

Using SNPs & STRs for Three Periods of Ancestry

As referenced in part one of this story, going back to J David Vance’s time scaled classification of of three levels of ancestry: Deep Ancestry, Lineages and Traditional Genealogy, SNP and STR mutations play various roles in analyzing Y-DNA in each of these time periods.

Three Periods of Ancestry: J David Lance Click for larger view

Deep ancestry time frames will, for the most part, rely on SNPs. [51] Both STRs and SNPs can be used within the time range of Lineages where one can trace a particular male line of unnamed ancestors. Traditional genealogy, if available, can help corroborate facts with regions or countries that common ancestors likely came from and where more than one surname may have been used. Within the time frame of traditional genealogy, all three sources of data can be helpful.

As DNA sequencing technology has improved and new tests have become available, such as the Full Y and Big Y tests, new mutations are being very rapidly discovered which blurs the line between the time frames that had been used to separate these types of tests.  In fact, now they are overlapping in time. SNPs are in some cases becoming useful at the traditional genealogical level.  These newly discovered family SNPs are relatively new, they emerged between the current generation and 1000 years ago. Although more individuals are completing Y-DNA tests, we should not expect to find huge numbers of these newly developed mutations in the population. [52]

As stated earlier, using both SNPs and STRs will potentially provide more specificity in tracing the patrilineal line from deep ancestry, through the middle area of lineages and into the more recent historical area of surnames and traditional genealogy. STR markers will generally mutate more frequently than SNPs.  SNP testing is getting better all the time and the advanced tests can now find SNPs every two or three generations, but STRs still mutate faster than that so sometimes you will have branches of the haplotree where no SNP mutations have been identified over a time period and you can not easily determine branching if you do not have the SNP branching points to navigate. However, STRs can show you where mutations have occurred which are more frequent than SNPs and they can mark branches that are not otherwise identified by SNPs.  So you can get a little more granularity out of STR testing. 

Similar to David Vance’s three periods of ancestry, Rob Spencer provides a graphic portrayal of tracing one’s ancestor’s based on three levels of research (illustration 16). Traditional genealogical paper trails and research can provide information in the recent past. For our family the paper trail start to run dry way before 300 years. Moreover, the onset of Welsh surnames is more recent than 1,000 years ago! Although the time spans for paper trails and surnames might vary, the illustration provides a good graphic relationship between traditional and DNA based genealogical research. The use of Y-DNA research can help trace unknown ancestors prior to the use of surnames, pinpoint possible regional areas where ancestors lived, and provide possible links to the recent past. Y-DNA research, coupled with archaeological and paleogenomic discoveries can also shed light on macro level connections to migration patterns that can be associated with genetic ancestors.

Illustration 16: Three Levels of Genealogical Research

Rob Spencer, Case Studies in Macro Genealology, Presentation for the New York Genealogical and Biographical Society, Slide Three, July 2021, http://scaledinnovation.com/gg/ext/NYG&B_webinar.pdf
Click for Larger View.

STR and SNP Tests

“The wise genealogist isn’t wedded to any particular technology or data source, but rather understands the strengths and limitations of SNPs, STRs, and paper genealogy, and uses each appropriately. Each can complement the others.” [53]

Similar to traditional genealogy, genetic genealogy is a continual process of gathering, updating and organizing information. Using single nucleotide polymorphism (SNP) test results along with short tandem repeat (STR) test results can provide a high level picture of ancestral patrilineage and possible discoveries of family ties in the recent past. [54] The relative strengths of SNP and STR tests are uniquely suited at each of the three levels of ancestral research.

Illustration 17 provides a depiction of the relative strengths of using SNP and STR tests for various historical periods of time. It also depicts the emerging overlap between the two tests as SNP tests have identified newer, more recent Y-DNA mutations. The illustration indicates that STR tests are very useful when analyzing test results between testers back to 1000 years or approximately 7 SNP mutations back from the tester.

Illustration 17: Using STR and SNP Tests at Different Historical Periods

Source: J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 1, 10 Oct 2019, https://youtu.be/RqSN1A44lYU page 11.
Click for Larger View.. 

Illustration 18 (below) provides a general explanation and some of the basic differences between SNPs and STRs. The top part of the image deals with STRs and the bottom deals with SNPs.  [55]

The example provides a illustrative string of DNA nucleotides starting with “GAAAGACTACT…” (basically one mirror side of the double helix). The string represents a segment of the DNA strand. There are three examples of STR positions that are marked by brown boxes, the first STR has five repeats and the second and third have three repeats each.  As discussed, STRs have names which can appear like the examples listed in the illustration:  DYS369, CDX, or FT2986.  Each of the STRs have specific positions on the Y chromosome.   When they are read, the number of repeats is reported. In this example, the first STR has a value of 5 and the second and third STRs have a value of 3 each.  Typically, STR values or Alleles will actually fall more into the 11, 12, 13, and higher number ranges.  A STR test may typically test 37, or 67, or 111 “markers”. Older STR tests might have had 12 or 25 markers tested. The tester will get as many of these documented STRs as the test will check.  In the Big Y testing testers get up to 838 STRs in the current Big Y 700 test.  

Illustration 18: Comparison of STR and SNP Tests

Source: J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 2, 3 Oct 2019 | Click for Larger View.

The bottom half of illustration 18 provides a look at SNPs. SNPs as indicated, examine specific single base pair positions in the DNA strand. They are highlighted in yellow in the illustration.  For these specific SNP positions, actual SNP names are used but their positions are illustrative and not literal. Every SNP has a name, a label. In some cases brand-new SNPs are discovered and initially named by the lab doing the testing.  They also have a position number that marks that SNP’s position on the Y-chromosome.  SNPs also have a “from” and a “to” value, so the allele value can go, for example, from “G” to “A” and these values are known, because there is a “reference genome”.  Based on the ancestral reference values, test results are then interpreted in terms of whether the SNP has mutated. In this illustrated example if the SNP position known as M269 has an the ancestral value of “G” and the test result is an “A” in this person’s DNA, we know that that SNP has mutated.  The SNP would be noted with a plus sign and this person is “M269 positive”.  

Continuing with the examples in illustration 18, going on to another SNP position, P312, the ancestral value is known to be an “A” and there is a “G”, so it is positive as well.  For the third SNP, called U106, located at a different position, the ancestral value is supposed to be a “T” and it is a “T” in the example, so the SNP has not mutated and it is labeled as negative. Based on the unique combination of tested SNPs, a tester is then placed on the Y-DNA haplotree.

Having more SNPs and STRs sampled and tested will increase the reliability and accuracy of the results. For STR tests, one can test individual STRs or obtain panel results of a series of STRs. There are tests called “individual” or “panel” SNP tests which check a certain set of SNP positions.

The individual and panel tests are contrasted with what is called “Next-Generation Sequencing” or another kind of test called “Whole Genome Sequencing”, which are usually abbreviated as NGS and WGS. These tests examine a range of regions on the Y chromosome.  Rather than target isolated SNPs, these tests report on any SNPs that are found in a specified area.  These tests typically report on SNPs that are traditionally isolated in the panel tests as well as report the results of testing a few million other base pairs.  That is how tests go “fishing” for new SNPs in a particular area of the Y chromosome where a SNP had not documented before and may result in novel findings.  The NGS and WGS tests similar to the Big Y 700 test tend to be the more expensive tests.  They provide results associated iwht the traditional Y DNA tests as well as the ‘exploratory’ results. The ‘fishing expedition’ tests are very powerful because they find new SNPs and report on new branches or subclades of existing haplogroups. They add to our knowledge of the haplotree where an individual or panel SNP test tends to be much cheaper but only goes after answering specific questions.  

The Next Part of the Story: The One-Two Punch of SNPs and STRs

The next part of the story provides the results of using SNP and STR tests as they pertain to the Griff(is)(es)(ith) patrilineage.

Sources

Feature Image of the story is a modified version of an image found in Study of ‘Exceptional Responders’ Yields Clues to Cancer, Potential Treatments, NIH Record, Dec 11, 2020, Vol. LXXII, No. 25, https://nihrecord.nih.gov/2020/12/11/study-exceptional-responders-yields-clues-cancer-potential-treatments

[1] The following research sources are an excellent start to get your bearings on the history of genetic genealogy, understanding the basic concepts associated with the field, gaining a general understanding of what genetic genealogy is and how to interpret results:

J David Vance is personally the first stop I would make to quickly learn about genetic genealogy. The following are great sources of his work:

J David Vance, The Genealogist Guide to Genetic Testing, 2020, self published book

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 1, 10 Oct 2019, https://youtu.be/RqSN1A44lYU

Part 1 of a 3-part introduction series to Y-DNA for genealogists. This first video focuses on “Why?” use Y-DNA for genealogy – what benefits does it offer and why should genealogists consider using Y-DNA as part of their research?

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 2, 3 Oct 2019 https://www.youtube.com/watch?v=mhBYXD7XufI&t=355s

Part 2 of a 3-part introduction series to Y-DNA for genealogists. This second video focuses on “What?” for Y-DNA for genealogy – what are STRs and SNPs, what is genetic distance, what is the haplotree, and other related questions

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 3, 10 Oct 2019  https://www.youtube.com/watch?v=03hRXVg9i1k&t=4s

Part 3 of a 3-part introduction series to Y-DNA for genealogists. This third video focuses on “How?” for Y-DNA for genealogy – how do I use the information provided by Y-DNA tests to advance my genealogy and/or my lineages?

David Reich’s seminal work in paleogenomics provides a lucid account on deep ancestry and ancient migratory history.

David Reich, Who We are and How We got Here, Ancient DNA and the New Science of the Human Past, New York: Vintage Books, 2018. This is an excellent overview of the history and recent accomplishments in the field of paleo-genetics or paleo-genomics.

Another source that provides historical background on the emergence genetic genealogy, see: Sheldon Krimsky, Understanding DNA Ancestry, Cambridge: Cambridge University Press, 2022

Y-DNA project help, International Society of Genetic Genealogy Wiki, This page was last edited on 28 October 2022, https://isogg.org/wiki/Y-DNA_project_help 

[2] Mathieson I, Scally A (2020) What is ancestry? PLoS Genet 16(3): e1008624. https://doi.org/10.1371/journal.pgen.1008624 https://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1008624

[3] J David Vance, The Genealogist Guide to Genetic Testing, 2020

There are some subtle and some not so subtle differences between ancestry research and genealogy research, but in the end the two are inextricably linked; they are symbiotic processes –

You Say Potato, I Say Potahto – You Say Ancestry Research, I Say Genealogy Research. Let’s Call the Whole Thing On, RecordClick professional Genealogists, https://www.recordclick.com/you-say-potato-i-say-potahto-you-say-ancestry-research-i-say-genealogy-research-lets-call-the-whole-thing-on/

[4] John Hawkes, When did humankind’s last common ancestor live? A surprisingly short time ago, 0 Jul 2022, Weblog, https://johnhawks.net/weblog/when-did-humankinds-last-common-ancestor-live/

[5] The genome is the entire set of DNA instructions found in a cell. In humans, the genome consists of 23 pairs of chromosomes located in the cell’s nucleus, as well as a small chromosome in the cell’s mitochondria. A genome contains all the information needed for an individual to develop and function. 

source: Genome: Definition, National Human Genome Research Institute, Page update 11 Aug 2022, https://www.genome.gov/genetics-glossary/Genome

[6] Autosomal DNA Statistics, International Society of Genetic Genealogy Wiki, Page was last edited 4 August 2022, Page accessed 14 Aug 2022, https://isogg.org/wiki/Autosomal_DNA_statistics

[7] Nicole Dyer, Charts for Understanding DNA Inheritance, 14 Aug 2019, Family Locket, Page accessed 10 Oct 2021, https://familylocket.com/charts-for-understanding-dna-inheritance/

[8] David Reich, Who We are and How We got Here, Ancient DNA and the New Science of the Human Past, New York: Vintage Books, 2018, pages 11-12

[9] Sheldon Krimsky, Understanding DNA Ancestry, Cambridge: Cambridge University Press, 2022, page 25

Working with STRs requires covering the topics of genetic distance and modal and ancestral haplotypes. Genetic distance , a concept created by Family Tree DNA (FTDNA), is a concept that ranks DNA matches or individuals according to how close they appear to be to each other.  Genetic distance is the result of calculating the number of mutation events which have occurred between two or more individuals. The more STR’s sampled and compared , the more reliable is the estimate of genetic distance.  Depending the the average rate of mutation for sampled markers, the number of differences between two samples (individuals) grows larger as the number of generations back to a common ancestor increases. FTDNA uses this idea to limit the number of matches shown in their match reports. If you have a 12 marker test, their cut off is a genetic distance of one (one mutation difference), for 37 markers the report cut off is at a genetical distance of 4, at 67 markers it is 7, and at 111 markers the report cut off s 10. 

Genetic Distance, Wikipedia, page was last edited on 29 June 2022, https://en.wikipedia.org/wiki/Genetic_distance

M. Nei, Genetic Distance, in  Standley Maloy & Kelly Hughes, ed, Brenner’s Encyclopedia of Genetics, second Edition, New York:Elsevier Inc, 2013, https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/genetic-distance

Genetic Distance, International Society of Genetic Genealogy, page was last edited on 31 January 2017, https://isogg.org/wiki/Genetic_distance

Modal Haplotype, International Society of Genetic Genealology Wiki, This page was last edited on 31 January 2017, https://isogg.org/wiki/Modal_haplotype

Ancestral Haplotype, International Society of Genetic Genealology Wiki, This page was last edited on 31 January 2017, https://isogg.org/wiki/Ancestral_haplotype

the Most Recent Common Ancestor, International Society of Genetic Genealology Wiki, This page was last edited on 31 January 2017, https://isogg.org/wiki/Most_recent_common_ancestor

[10] The illustration of a haplotree and a family tree is from: Understanding DNA, FamilyTreeDNA , https://www.familytreedna.com/understanding-dna.aspx?intent=&gclid=Cj0KCQjwl92XBhC7ARIsAHLl9amGAQgLA88oTpLktNa4qWNr8MUPmb6aApGoSrvXL98o-plhnoNw6SgaAvSGEALw_wcB

The dendrogram is an illustration of the comparative analysis of results of males who completed Y-DNA tests from Family Treee DNA (FTDNA) who share common genetic ancestors .

[11] What Percentage of Native American Do You Have To Be To Enroll With a Tribe?, Powwows.com,  January 8th, 2018, Last Updated on: April 4th, 2022, Page accessed 6 May 2021, https://www.powwows.com/much-percentage-native-american-enroll-tribe/

[12] There are countless articles documenting personal experiences associated with taking and interpreting genetic tests from the major companies that illustration the problem of confusing genealogical, genetic and cultural ancestry. Here are a few:

Newton, Maud, America’s Ancestry Craze: Making sense of our family-tree obsession, Harper’s Magazine, Page accessed 5 Jun 2021

Wagner, Alex, A Journalist Seeks Out Her Roots but Finds Few Answers in the Soil, NPR Terry Gross Interview, 30 April 30 2018, Page accessed 11 Mar 2021

Dava Stewart, Problems with Ancestry DNA Analyses, Dark Daily, Oct 12, 2018

Leavenworth, Stuart, Ancestry wants your spit, your DNA and your trust. Should you give them all three?, 29 May 2018

Brown, Kristen, How DNA Testing Botched My Family’s Heritage, and Probably Yours, Too, 16 Jan 2018, Page accessed 11 Mar 2021

Raffi Khatchadourian, How Your Family Tree Could Catch a Killer, The New Yorker, November15, 2021

Resnick, Brian, The limits of ancestry DNA tests, explained, Vox, Updated 23 May 23 2019, Page accessed 11 Mar 20212

Saey, Tina , What I actually learned about my family after trying 5 DNA ancestry tests, Sience News, 13 Jun 2018, Page accessed 12 Jan 2021

Saey, Tina, What genetic tests from 23andMe, Veritas and Genos really told me about my health, Science News, 22 May 2018

Saey, Tina, Consumer DNA testing promises more than it delivers, Science News, 22 may 2018

Barry Starr, 5 Myths About Ancestry DNA Estimates, Blog article at Ancestry.com, 27 Sep 2021, Accessed 18 Mar 2022

Maya Jasanoff, Obsession with Ancestry Has Some Twisted Roots, 9 May 2022, New Yorker Newsletter, Published in the print edition of the May 9, 2022, issue, with the headline “Ancestor Worship.”

[13] Racimo F, Sikora M, Vander Linden M, Schroeder H, Lalueza-Fox, C, Beyond broad strokes: sociocultural insights from the study of ancient genomes. Nat Rev Genet. 2020 Jun; 21(6): 355-366. doi: 10.1038/s41576-020-0218-z. Epub 2020 Mar 3. PMID: 32127690. https://www.nature.com/articles/s41576-020-0218-z#citeas

[14] Bridget Alex and Priya Moorjani, DNA dating: How molecular clocks are refining human evolution’s timeline, 6 Apr 2017, the Conversation, https://theconversation.com/dna-dating-how-molecular-clocks-are-refining-human-evolutions-timeline-65606

[15] X-DNA is usually tested along with other chromosomes as part of an atDNA test. Until recently X-DNA analysis tools were only available as third-party tools and at 23andMe. Even with access to the X-DNA data, the lack of tools and the different inheritance pattern for X-DNA have caused many genealogists to ignore X-DNA data when it can narrow down the lines to be searched, allowing for efficient use of our research time. See for example: Debbie Parker Wayne, Using X-DNA for genealogy, National Genealogical Society Magazine, July-September 2014 · volume 40, number 3, Pages 57-61. https://www.ngsgenealogy.org/wp-content/uploads/2019/05/Debbie-Parker-Wayne-Using-X-DNA-for-Genealogy-National-Genealogical-Society-Magazine-40-July-September-2014-57-61.pdf

[16] Chelsea Toledo and Kirstie Saltsman, Genetics by the numbers, National Insitute of General Medical Sciences, Posted 12 Jun 2012, https://www.nigms.nih.gov/education/Inside-Life-Science/Pages/genetics-by-the-numbers.aspx

Length of Human DNA, Dodona – online exercise platform for learning to code, Ghent University, Page accessed 20 Jun 2022, https://dodona.ugent.be/en/activities/434589381/

Elizabeth Penesi, Watch the human genome fold itself in four dimensions, Science, 10 Oct 2017, Page accessed 6 May 2022, https://www.science.org/content/article/watch-human-genome-fold-itself-four-dimensions

Veratas Genetics, Size Matters: A Whole Genome is 6.4B Letters, Veratas Genetics, 28 Jul 2017, Page accessed 27 Jul 2022, https://www.veritasgenetics.com/our-thinking/whole-story/

Fundamental Concepts of Genetics and about the Human Genome, Eupedia, Page accessed 7 Jul 2022, https://www.eupedia.com/genetics/human_genome_and_genetics.shtml

Hannah Ashworth, How Long is Your DNA? BBC Science Focus Magazine, Page accessed 14 Jun 2022, https://www.sciencefocus.com/the-human-body/how-long-is-your-dna/

Ruairi J. Mackenzie, DNA vs RNA – 5 Key differences and Comparison Technology Networks Genomics Research 18 Dec 2020, Updated31 Mar 2021  https://www.technologynetworks.com/genomics/lists/what-are-the-key-differences-between-dna-and-rna-296719

Genetics Glossary, International Society of Genetic Genealogy Wiki, This page was last edited on 9 October 2021, page accessed on 10 Oct 2021

[17] Fundamental Concepts of Genetics and about the Human Genome, Eupedia, page accessed 3 Feb 2021, https://www.eupedia.com/genetics/human_genome_and_genetics.shtml

Sheldon Krimsky, Understanding DNA Ancestry, Cambridge: Cambridge University , 2022, Page 18

[18] Jake Buehler, The Complex Truth About ‘Junk DNA’, Quanta Magazine, 1 Sep 2021, https://www.quantamagazine.org/the-complex-truth-about-junk-dna-20210901/

Non-coding DNA, Wikipedia, This page was last edited on 2 September 2022, https://en.wikipedia.org/wiki/Non-coding_DNA

[19] Sheldon Krimsky, Understanding DNA Ancestry, Cambridge: Cambridge University , 2022, Page 18

[20] Non-Coding DNA, AncestryDNA Learning Hub, https://www.ancestry.com/c/dna-learning-hub/junk-dna

Wojciech Makalowski, What is junk DNA, and what is it worth?, Scientific American, 12 Feb 2007, https://www.scientificamerican.com/article/what-is-junk-dna-and-what/

[21] Khushi Jain, Karyotype and Karyotyping – definition, Procedure, and Applications, 5 May 2022, The Biology Notes, Page accessed 8 Aug 2022, https://thebiologynotes.com/karyotype-karyotyping/

Samanthi, Difference Between Karyotype and Idiogram, Difference Between, August 27, 2019, page accessed 4 Aug 2022, https://www.differencebetween.com/difference-between-karyotype-and-idiogram/

Human Genome, Wikipedia, This page was last edited on 1 September 2022, https://en.wikipedia.org/wiki/Human_genome

[22] Ancestry Information Markers, National Human Genome Research Institute, https://www.genome.gov/genetics-glossary/Ancestry-informative-Markers

Joon-Ho You, Janelle S. Taylor, Karen L. Edwards, Stephanie M. Fullerton, What are our AIMs? Interdisciplinary Perspectives on the Use of Ancestry Estimation in Disease Research, National Library of Medicine, 2012 Nov 5. doi: 10.1080/21507716.2012.717339

Huckins, L., Boraska, V., Franklin, C. et al. Using ancestry-informative markers to identify fine structure across 15 populations of European origin. Eur J Hum Genet 22, 1190–1200 (2014). https://doi.org/10.1038/ejhg.2014.1

[23] Leonard M. Fleck, 22 Apr 2021, If Whole Genome Sequencing is So Cheap and Quick, Why Shouldn’t Everyone Have It Done?, Michigan State Bioethics, center for Bioethics and Social Justice at Michigan State University, https://msubioethics.com/2021/04/22/whole-genome-sequencing-why-shouldnt-everyone-have-it-done-fleck/

Kris A. Wetterstrand, The Cost of Sequencing a Human Genome, National Human Genome Research Institute, National Institute of Health, 1 Nov 2021, https://www.genome.gov/about-genomics/fact-sheets/Sequencing-Human-Genome-cost

Emily Mullen, The Era of Fast, Cheap Genome Sequencing Is Here, 29 Sep 2022, Wired, https://www.wired.com/story/the-era-of-fast-cheap-genome-sequencing-is-here/

[24] Sheldon Krimsky, Understanding DNA Ancestry, Cambridge: Cambridge University , 2022, Page 23

Blaine Bettinger, The Family Tree Guide to DNA Testing and Genetic Genealogy, 2nd Edition, Penguin Random House LLC, 2016

Diana Elder, NicoleDyers and Robin Wirthlin, Research Like a Pro with DNA: A Genealogist’s Guide to Finding and Confirming Ancestors with DNA Evidence, Highland UT: Family Locket Books, 2021

R.C. Lewontin, The Apportionment of Human Diversity, Evolutionary Biology, 6:381, 1972

K.L. Hunley, G.S. Cabana, J.C. Long The Apportionment of Human Diversity Revisited, American Jounral of Physical Anthropology, 160: 5561-569

Noah A. Rosenberg, Jonathan K. Pritchard, James L. Weber, Howard M. Can, Kenneth K. Kidd, Lev A. Zhivotovsky, Marcus W. Feldman , Genetic Structure of Human Populations, Science, 20 Dec 2002, Vol 298, Issue 5602, pp. 2381-2385, https://www.science.org/doi/abs/10.1126/science.1078311

[25] David Reich, Who We are and How We got Here: Ancient DNA and the New Science of the Human Past, New York: Vintage Books, 2018, page 4

[26] J David Vance, The Genealogist Guide to Genetic Testing, 2020, page 221

[27] J David Vance, The Genealogist Guide to Genetic Testing, 2020, Chapter 13

[28] Chris Gunter, Single Nucleotide Polymorphisms (SNPS), 10 May 2022, National Human Genome Research Institute, https://www.genome.gov/genetics-glossary/Single-Nucleotide-Polymorphisms

What are single nucleotide polymorphisms (SNPs)?, MedlinePlus, National Library of Medicine, https://medlineplus.gov/genetics/understanding/genomicresearch/snp/

Single-nucleotide polymorphism, Wikipedia, page was last edited on 11 November 2022, https://en.wikipedia.org/wiki/Single-nucleotide_polymorphism

SNP’s, Genetics Generation, https://knowgenetics.org/snps/

Making SNPs Make sense, Learn Genetics, Genetic Science Learning Center, https://learn.genetics.utah.edu/content/precision/snips

How do geneticists indicate the location of a gene?, Page last updated 26 Mar 2021, National, MedlinePlus,  Library of Medicine, https://medlineplus.gov/genetics/understanding/howgeneswork/genelocation/

[29] See: Private variant vs novel variant vs singleton, FamilyTree DNA Forum , 31 May 2021, 330714-private-variant-vs-novel-variant-vs-singleton

  1. A novel variant is a new SNP.
  2. A private variant is also a new SNP, but one found in a particular line, not yet among other testers. It seems that a private variant is also a novel variant.
  3. A singleton is unique to one tester and his haplogroup; the only difference in the definition between this and a private variant seems to be the added condition of how a singleton is unknown where it is placed among other subclades.

Novel SNP, YFullDefinitions, https://www.yfull.com/faq/definitions/

[30] J David Vance, The Genealogist Guide to Genetic Testing, 2020, self published book, Chapters 6 and 13

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 2, 3 Oct 2019 https://www.youtube.com/watch?v=mhBYXD7XufI&t=355s

Part 2 of a 3-part introduction series to Y-DNA for genealogists. This second video focuses on “What?” for Y-DNA for genealogy – what are STRs and SNPs, what is genetic distance, what is the haplotree, and other related questions

[31] STRs vs SNPs, Multiple DNA Personalities, DNAeXplained – Genetic Genealogy, 10 Feb 2014, https://dna-explained.com/2014/02/10/strs-vs-snps-multiple-dna-personalities/

[32] YHRD R68, Locus Information on DYS393, https://yhrd.org/details/locus_information/DYS393DYS393, STRBase (SRD-130), National Institute of Standards and Technology, last updated 7 Feb 2008, https://strbase.nist.gov//str_y393.htm

[33] STR Analysis, Wikipedia, page was last edited 25 Oct 2022, https://en.wikipedia.org/wiki/STR_analysis

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Terry Taylor, What is STR Analysis?, 2 Mar 2011, This article appeared in NIJ Journal Issue 267, March 2011, as a sidebar to the article Extending the Time to Collect DNA in Sexual Assault Cases by Terry Taylor.

Has Fan, Jai-You Chu, A Brief Review of Short Tandem RepeatMutation, Genomics Proteomics Bioinformatics. 2007; 5(1): 7–14. Published online 2007 Jun 15. doi: 10.1016/S1672-0229(07)60009-6

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Bits de Cliencia Official, The Best Review of STRs (Short tandem repeat) Mutation | Applied to the Forensic Video, 23 Sep 2015, https://www.youtube.com/watch?v=9bEAJYnVVBA A concise video explaining the reliability of forensic DNA.

Fundamental Concepts of Genetics and about the Human Genome, Eupedia, page accessed 3 Feb 2021, https://www.eupedia.com/genetics/human_genome_and_genetics.shtml

Genetics Glossary, International Society of Genetic Genealogy Wiki, This page was last edited on 9 October 2021, https://isogg.org/wiki/Genetics_Glossary

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 1, 10 Oct 2019, https://youtu.be/RqSN1A44lYU  Part 1 of a 3-part introduction series to Y-DNA for genealogists. This first video focuses on “Why?” use Y-DNA for genealogy – what benefits does it offer and why should genealogists consider using Y-DNA as part of their research?

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 2, 3 Oct 2019 https://www.youtube.com/watch?v=mhBYXD7XufI&t=355s  Part 2 of a 3-part introduction series to Y-DNA for genealogists. This second video focuses on “What?” for Y-DNA for genealogy – what are STRs and SNPs, what is genetic distance, what is the haplotree, and other related questions

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 3, 10 Oct 2019  https://www.youtube.com/watch?v=03hRXVg9i1k&t=4s Part 3 of a 3-part introduction series to Y-DNA for genealogists. This third video focuses on “How?” for Y-DNA for genealogy – how do I use the information provided by Y-DNA tests to advance my genealogy and/or my lineages?

J David Vance, The Genealogist Guide to Genetic Testing, 2020 https://www.amazon.com/Genealogists-Guide-Testing-Genetic-Genealogy/dp/B085HQXF4Z/ref=tmm_pap_swatch_0?_encoding=UTF8&qid=&sr=

Michael Hébert, Y-DNA Testing Company STR Marker Comparison Chart, Last updated on January 08, 2012, http://www.gendna.net/ydnacomp.htm

Kayser et al. (2004), A Comprehensive Survey of Human Y-Chromosomal Microsatellites Am. J. Hum. Genet., 74 1183-1197. NB online only data file

Krahn, Thomas. “Y-STR fingerprint – Panels” (PDF). Price List DNA-Fingerprint – Genealogy Testing Services. Retrieved 11 August 2012.

Butler, John M. (9 January 2012). “Y-Chromosome STRs”Short Tandem Repeat DNA. NIST Standard Reference Database SRD 130. Retrieved 11 August 2012.

Butler, John; Kline, Decker (2009-06-29). “Summary List of Y Chromosome STR Loci and Available Fact Sheets”. NIST Standard Reference Database SRD 130. Retrieved 11 August 2012.

State of the Y-Chromosome for Human Identity Testing: John Butler talk at Canadian Forensic DNA Technology Workshop (June 8, 2005)

L. Gusma ̃, J.M. Butler, A. Carracedo, P. Gill, M. Kayser, W.R. Mayr, N. Morling, M. Prinz, L. Roewer, C. Tyler-Smithj, P.M. Schneider, DNA Commission of the International Society of Forensic Genetics (ISFG): An update of the recommendations on the use of Y-STRs in forensic analysis, Forensic Science International 157 (2006) 187–197, https://strbase.nist.gov//pub_pres/ISFG_YSTRupdate_FSI2006.pdf

Y STR Positions along Y Chromosome, STRBase (SRD-130) National Institute of Standards and technology,, U.S. Department of Commerce, https://strbase.nist.gov//ystrpos1.htm

Y-STR Reference Bibliography, STRBase (SRD-130) National Institute of Standards and technology, U.S. Department of Commerce, https://strbase.nist.gov//ystr_ref.htm

J David Vance, The Genealogist Guide to Genetic Testing, 2020, Chapter 13

SNP-based age analysis methodology: a summary, Summarised description of the age analysis pipeline — Iain McDonald, June 2017, https://www.jb.man.ac.uk/~mcdonald//genetics/pipeline-summary.pdf

Albers PK, McVean G (2020) Dating genomic variants and shared ancestry in population-scale sequencing data. PLoS Biol 18(1): e3000586. https://doi.org/10.1371/journal.pbio.3000586

National Library of Medicine, Genetics, What are single nucleotide polymorphisms (SNPs)? Page accessed 1 Oct 2022, https://medlineplus.gov/genetics/understanding/genomicresearch/snp/

Dmitry Adamov, Sergey Karzhavin, Vadim Urasin, Vladimir M. Gurianov, vladimir Tagankin, Defining a New Rate Constant for Y-Chromosome SNPs based on Full Sequencing Data, 21 March 2015, The Russian Journal of Genetic Genealogy (Русская версия): Том 7, №1, 2015 год ISSN: 1920-2997 http://ru.rjgg.org

[34] J David Vance, The Genealogist Guide to Genetic Testing, 2020, Chapter 17

[35] Roberta Estes, STRs vs SNPs, Multiple DNA Personalities, DNAeXplained – Genetic Genealogy, 10 Feb 2014, https://dna-explained.com/2014/02/10/strs-vs-snps-multiple-dna-personalities/

Unique-event polymorphism, International Society of Genetic Genealogy Wiki, This page was last edited on 23 February 2021, https://isogg.org/wiki/Unique-event_polymorphism

Unique-event polymorphism. Wikipedia, This page was last edited on 21 June 2020. Unique-event_polymorphism

[36] J David Vance, The Genealogist Guide to Genetic Testing, 2020, Chapter 6

With enough time and enough possible combinations of mutations, it is possible to end up with matching or closely matching Y-DNA marker results in individuals who do not share a “recent” common ancestor on the male line. Convergence is more plausible in individuals belonging to common haplogroups. See, Convergence, International Society of Genetic Genealogy Wiki, Page last updated 6 Dec 2018

Rob Spencer has a cogent explanation of convergence: See quote below and reference: Robert W. Spencer Convergence, Tracking Back: a website for genetic genealogy tools, experimentation, and discussion, no date, page accessed 3 May 2022.

“The men in question actually are related — this is key — but in a particular way and usually long before the genealogical time span of a couple of hundred years. A group of modern descendants might not care if they have a common ancestor who lived in 1000 AD — but it really matters.”

[37] Unique Event Polymorphism, Bionity.comhttps://www.bionity.com/en/encyclopedia/Unique_event_polymorphism.html

[38] Roberta Estes Y-700: The Forefront of Y Chromosome Testing, 7 Jun 2017, FamilyTree DNA Blog, https://blog.familytreedna.com/human-y-chromosome-testing-milestones/

Roberta Estes, FamilyTree DNA Blog, Why Big Y-700? 21 Oct 2022, https://blog.familytreedna.com/why-big-y-700/

Roberta Estes,    Working with Y DNA – Your Dad’s Story, FamilyTree DNA Blog. 5 Jun 2017, https://dna-explained.com/2017/06/05/working-with-y-dna-your-dads-story/

[39] J David Vance, The Genealogist Guide to Genetic Testing, 2020, Chapter 15

[40] SNPs are given names based on an abbreviation that indicates the lab or research team that discovered the SNP and a number that indicates the order in which it was discovered. The prefix, the first letter or group of letters after the main alpha Haplogroup letter identifies the lab or analysis company which first discovered the SNP or was really the first to decide that the mutation at that position on the Y- chromosome was worthy of a name. 

SNPs development indicated by beginning letters:
A = Thomas Krahn, MSc (Dipl.-Ing.), YSEQ.net, Berlin, Germany
ACT = Ancient-Tales Institute of Anthropology, Enlighten BioTech Co., Ltd., Shanghai, China
AD = Dr. Mohammed Al Sharija, Ministry of Education (Kuwait)
AF = Fernando Mendez, Ph.D., University of Arizona, Tucson, Arizona
ALK = Ahmad Al Khuraiji
AM or AMM = Laboratory of Forensic Genetics and Molecular Archaeology, UZ Leuven, Leuven, Belgium
B = Estonian Genome Centre
BY = Big Y testing (next generation sequencing) discovered with the BigY-500, Family Tree DNA, Houston, Texas
BZ = Q-M242 Project, Family Tree DNA, Houston, TX. SNPs named in honor of Barry Zwick.
CTS = Chris Tyler-Smith, Ph.D., The Wellcome Trust Sanger Institute, Hinxton, England
DC = Dál Cais, an Irish group believed to be descended from Cas, b. CE 347, related to SNP R-L226; Dennis Wright
DF = anonymous researcher using publicly available full-genome-sequence data, including 1000 Genomes Project data; named in honor of the DNA-Forums.org genetic genealogy community
E = Bulat Muratov
F = Li Jin, Ph.D., Fudan University, Shanghai, China
F* = Chuan-Chao Wang, Hui Li, Fudan University, Shanghai, China (Beginning letter F; second letter Haplogroup, i.e. FI is Fudan Haplogroup I)
FGC = Full Genomes Corp. of Virginia and Maryland
FT = Big Y testing (next generation sequencing)discovered with the Big Y-700, Family Tree DNA, Houston, Texas
G = Verónica Gomes, IPATIMUP Instituto de Patologia e Imunologia Molecular da Universidade do Porto (Institute of Molecular Pathology and Immunology of the University of Porto)
GG=Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
IMS-JST = Institute of Medical Science-Japan Science and Technology Agency
JD = David Stedman using Big Y and other NGS sources.
JFS = John Sloan
JN = Jakob Nortsedt-Moberg
K = Youngmin JeongAhn, Ph.D; Education: Seoul National University and the University of Arizona
KHS = Functional Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology
KL = Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
KMS = Segdul Kodzhakov; Albert Katchiev; Anatole Klyosov; Astrid Krahn; Thomas Krahn; Bulat Muratov; Chris Morley; Ramil Suyunov; Vadim Sozinov; Pavel Shvarev; SF “National clans DNA project”; EHP “Suyun” Ph.D. of Technical Science; Prof. Elsa Khusnutdinova, Sc.D. of Biological Sciences, Laboratory of Molecular Human Genetics, Institute of Biochemistry and Genetics, Ufa Research Centre, Russian Academy of Sciences
L = Thomas Krahn, MSc (Dipl.-Ing.) formerly of Family Tree DNA’s Genomics Research Center; snps named in honor of the late Leo Little
M = Peter Underhill, Ph.D. of Stanford University
MC = Christopher McCown, University of Florida; Thomas Krahn, MSc (Dipl.-Ing.), YSEQ.net, Berlin, Germany
MF = 23mofang BioTech Co., Ltd., Chengdu, China
MPB = Thomaz Pinotti and Fabrício R. Santos, Laboratório de Biodiversidade e Evolução Molecular (LBEM), Universidade Federal de Minas Gerais, Brazil
MZ = Hamma Bachir, Ph.D., E-M183 Project
N = The Laboratory of Bioinformatics, Institute of Biophysics, Chinese Academy of Sciences, Beijing
NWT = Northwest Territory, Theodore G. Schurr, Ph.D., Laboratory of Molecular Anthropology, University of Pennsylvania, Philadelphia, PA
P = Michael Hammer, Ph.D. of University of Arizona
Page, PAGES or PS = David C. Page, Whitehead Institute for Biomedical Research
PF = Paolo Francalacci, Ph.D., Università di Sassari, Sassari, Italy
PH = Pille Hallast, Ph.D., University of Leicester, Department of Genetics, United Kingdom
PK = Biomedical and Genetic Engineering Laboratories, Islamabad, Pakistan
PLE = Stanislaw Plewako, M. Sci, Baltic Sea DNA Project.
PR = Primate (gorilla and chimpanzee), Thomas Krahn’s WTTY. Some sources have not provided new names when same mutation found independently in humans.
RC = Major Rory Cain, BA(hons), BEd, BSc.
S = James F. Wilson, D.Phil. at Edinburgh University
SA = South America, Theodore G. Schurr, Ph.D., Laboratory of Molecular Anthropology, University of Pennsylvania, Philadelphia, PA
SK = Mark Stoneking, Ph.D., Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
SUR = Southern Ural; SF “National clans DNA project”; B.A. Muratov; EHP “Suyun” Ph.D. of Technical Sciences; Ramil Suyunov; Prof. E.K. Khusnutdinova, Sc.D. of Biological Sciences, Laboratory of Molecular Human Genetics, Institute of Biochemistry and Genetics, Ufa Research Centre Russian Academy of Sciences; Alexander Zolotarev; Igor Rozhanskii; Bayazit Yunusbaev, Institute of Biochemistry and Genetics, Ufa Research Centre, Russian Academy of Sciences
TSC = Gudmundur A. Thorisson and Lincoln D. Stein, The SNP Consortium, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY
U = Lynn M. Sims, University of Central Florida; Dennis Garvey, Ph.D. Gonzaga University; and Jack Ballantyne, Ph.D., University of Central Florida
V = Rosaria Scozzari and Fulvio Cruciani, Dipartimento di Biologia e Biotecnologie “Charles Darwin” , Sapienza Università di Roma, Rome, Italy.
VK = Viacheslav Kudryashov.
VL = Vladimir Volkov, Tomsk University, Russia
Y = Y Full Team (Russian) using data from published and commercial next-generation sequencing samples
YP = SNPs identified by citizen scientists from genetic tests, then submitted to the Y Full team for verification.
YSC = Thomas Krahn, MSc (Dipl.-Ing.) formerly of Family Tree DNA’s Genomics Research Center
Z = Gregory Magoon, Ph.D., Richard Rocca, Vince Tilroe, David F. Reynolds, Bonnie Schrack, Peter M. Op den Velde Boots, Ray H. Banks, Roman Sychev, Victar Mas, Steve Fix, Christian Rottensteiner, Alexander R. Williamson, Ph.D., John Sloan and an anonymous individual, independent researchers of publicly available whole genome sequence datasets, and Thomas Krahn, MSc (Dipl.-Ing.), with support from the genetic genealogy community.
ZP = Peter M. Op den Velde Boots, David Stedman using Big Y and other NGS sources.
ZQ = Gabit Baimbetov, Nurbol Baimukhanov “ShejireDNA project” and other members of the project.
ZS = Gregory Magoon, Ph.D., Aaron Salles Torres from samples from Full Genomes and the Big Y.
ZW = Michael W. Walsh using Big Y.
ZZ = Alex Williamson. Mutations in palindromic regions. Each ZZ prefix represents two possible SNP locations.

Source: Y-DNA Haplogroup Tree 2019-2020, version 15.73, 11 July 2020, Internal Society of Genetic Genealogy, https://isogg.org/tree/

A SNP discovered or identified by YFull starts with a “Y”; a SNP starting with a “BY” or “FT” was named by Family Tree DNA, a “FGC” SNP was named by Full Genomes Corporation, and an “A” SNP was named by YSEQ. An ‘M’ stands for the Human Population Genetics Laboratory at Stanford University.

[41] John M. Butler, Recent developments in Y-single tandem repeat and Y-single nucleotide polymorphism analysis; Forensic Science Review Volume 15, Number Two, July 2003, https://strbase.nist.gov//pub_pres/Butler2003b.pdf

Peter Gill, Oskar Hansen, Hinda Haned, Øyvind Bleka, Corina Benschop in Forensic Practitioner’s Guide to the Interpretation of Complex DNA Profiles, 2020

[42] At FamilyTreeDNA, the Big Y 700 test tests up to 838 Y-chromosome DNA short tandem repeat (STR) markers. The following link provides information on all markers offered in these test panels 

Y-STR Results Guide, FamilyTree DNA Help Center, https://help.familytreedna.com/hc/en-us/articles/4408063356303-Y-STR-Results-Guide-#panel-1-1-12–0-0

[43] Publications and Presentations from the NIST Human Identity Project Team (DNA Forensics and Biometrics) SSTR Base (SRD-130), National Institute of Standards and Technology, U.S. Department ope Commerce, Last Updated: 06/29/2009. https://strbase.nist.gov//NISTpub.htm

John M. Butler, in Advanced Topics in Forensic DNA Typing: Methodology, 2012 in John Butle, Forensic DNA Typing: Methodology, 2012 New York: Academic Press, Elsevier Inc.

Jay A. Siegel, Pekka J. Saukko and Max M. Houck, Editors in Chief, Encyclopedia of Forensic Schemes, 2013, Elsevier Ltd., https://www.sciencedirect.com/referencework/9780123821669/encyclopedia-of-forensic-sciences

S. Short, DNA Basic Principles, in Encyclopedia of Forensic and Legal Medicine (Second Edition), 2016 https://doi.org/10.1016/B978-0-12-800034-2.00151-8

[44] John Butler, Margaret C. Kline, and Amy E. Decker, Addressing Y-Chromosome Short Tandem Repeat Allele Nomenclature , Journal of Genetic Genealogy, 4(2): 125-148, 2008, https://strbase.nist.gov//pub_pres/Butler2008-JoGG-YSTR-nomenclature.pdf

John Butler, Recent Developments in Y-Short Tandem Repeat and Y-Single Nucleotide Polymorphism Analysis Forensic Science Review 15:91, 2003,   https://strbase.nist.gov//pub_pres/Butler2003b.pdf

Hanson EK, Ballantyne J (2006) Comprehensive annotated STR physical map of the human Y chromosome: forensic implications Legal Med., 8:110-120; see also http://ncfs.ucf.edu/ystar/ystar.html

Kayser M, Kittler R, Ralf A, Hedman M, Lee AC, Mohyuddin A, Mehdi SQ, Rosser Z, Stoneking M, Jobling MA, Sajantila A, Tyler- Smith C (2004) A comprehensive survey of human Y-chromosomal microsatellites. , 74(6):1183-1197.

See: List of Y-STR markers, Wikipedia, page was last edited on 12 April 2022, https://en.wikipedia.org/wiki/List_of_Y-STR_markers

Hao Fan, A Brief Review of Short Tandem Repeat Mutation, Genomics, Proteomics & Bionformatics, Volume 5, Issue 1, 2007, Pages 1-7, https://www.sciencedirect.com/science/article/pii/S1672022907600096

Summary List of Y chromosome STR Loci and Available Fact Sheets, (STRBase (SRD-130) National Institute of Standards and Technology, U.S. Department ope Commerce, Last Updated: 06/29/2009 https://strbase.nist.gov//ystr_fact.htm

For general information on Short Tandem Repeats:

Christian M. Ruitberg, Dennis J. Reeder, John M. Butler, STRBase: a short tandem repeat DNA database for the human identity testing community, Nucleic Acids Research, Aug 31 2001, Vol 29, No. 1, 320-322, https://strbase.nist.gov/images/STRBase.pdf

Y STR Positions along Y Chromosome, STRBase (SRD-130),  National Institute of Standards and Technology, U.S. Department of Commerce, https://strbase.nist.gov//ystrpos1.htm

Michael L. Hébert, Y-DNA Testing Company STR Marker Comparison Chart, Last updated on January 08, 2012, http://www.gendna.net/ydnacomp.htm

Y-STR Results Frequently Asked Questions, Family Tree DNA Help Center, https://help.familytreedna.com/hc/en-us/articles/4408071453711-Y-STR-Results-Frequently-Asked-Questions-#what-are-the-differences-between-snps-and-strs–0-0

J David Vance, Chapter 5 Introducing Short Nucleotide Polymorphisms (SNPs) & Chapter 13 The Genetics of STRs and SNPs, The Genealogist Guide to Genetic Testing, 2020

Wyner N, Barash M, McNevin D. Forensic Autosomal Short Tandem Repeats and Their Potential Association With Phenotype. Front Genet. 2020 Aug 6;11:884. doi: 10.3389/fgene.2020.00884 . PMID: 32849844; PMCID: PMC7425049. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7425049/

YHRD R68, Mutation Rates, https://yhrd.org/pages/resources/mutation_rates

The following reference is a bit dated but accurate. It reflects the relative position of various STR markers on the Y chromosome:

Chromosomal Locations for DNA Typing Markers, STRBase (SRD – 130), National Institute of Standards and Technology, U.S. Department of Commerce, Last updated: 11/17/2011 https://strbase.nist.gov/chrom.htm

Y STR Positions along Y chromosome, STRBase (SRD – 130), National Institute of Standards and Technology, U.S. Department of Commerce  , https://strbase.nist.gov/ystrpos1.htm

Butler, J.M., Kline, M.C., Decker, A.E. (2008) Addressing Y-chromosome short tandem repeat (Y-STR) allele nomenclature. Journal of Genetic Genealogy 4(2): 125-148

Publications and Presentations from the NIST Human Identity Project Team (DNA Forensics and Biometrics) SSTR Base (SRD-130), National Institute of Standards and Technology, U.S. Department ope Commerce, Last Updated: 06/29/2009. https://strbase.nist.gov//NISTpub.htm

Summary List of Y Chromosome STR Loci and Available Fact Sheets, STRBase (SRD-130),  National Institute of Standards and Technology, U.S. Department of Commerce, Last Updated: 06/29/2009   https://strbase.nist.gov//ystr_fact.htm

Y STR Positions along Y Chromosome, STRBase (SRD-130),  National Institute of Standards and Technology, U.S. Department of Commerce, https://strbase.nist.gov//ystrpos1.htm

[45] J David Vance, Chaper Chapter 5 Introducing Short Nucleotide Polymorphisms (SNPs) & Chapter 13 The Genetics of STRs and SNPs, The Genealogist Guide to Genetic Testing, 2020

[46] Fotsing SF, Margoliash J, Wang C, Saini S, Yanicky R, Shleizer-Burko S, Goren A, Gymrek M. The impact of short tandem repeat variation on gene expression. Nat Genet. 2019 Nov;51(11):1652-1659. doi: 10.1038/s41588-019-0521-9. Epub 2019 Nov 1. PMID: 31676866; PMCID: PMC6917484. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6917484/pdf/nihms-1540630.pdf

[47] Y-STR Results Guide, FamilyTree DNA Help Center, https://help.familytreedna.com/hc/en-us/articles/4408063356303-Y-STR-Results-Guide-#panel-4-48-60–0-4

Caleb Davis, Michael Sager, Göran Runfeldt, Elliott Greenspan, Arjan Bormans, Bennett Greenspan, and Connie Bormans, Big Y 700 White paper, March 27, 2019, https://blog.familytreedna.com/wp-content/uploads/2018/06/big_y_700_white_paper_compressed.pdf

Marty Brady, Y Chromosomes and the SNPs STRs, May 16 2020 Presentation, Albuquerque Genealogical Society, Ychromosome_slides.pdf

Ian McDonald, Exploring new Y-DNA Horizons with Big Y-700  19 Oct 2019, presentation was originally given as part of Genetic Genealogy Ireland 2019. https://familytreewebinars.com/webinar/exploring-new-y-dna-horizons-with-big-y-700/]

[48] The DYS, DYZ, and DYF prefixes for STRs are part of the scientific name for a short tandem repeat (STR) found on the Y chromosome. STR markers are named according to guidelines published by the HUGO Gene nomenclature committee (HUGO). For Y-DNA STR tests:

  • D stands for DNA.
  • Y stands for Y chromosome.
  • S, Z, and F stand for the complexity of the repeat segment as follows:
    • S is a unique segment.
    • Z is a number of repetitive segments at one site.
    • F is a segment that has multiple copies on the Y chromosome.

The FTY prefix stands for “Family Tree Y”. This prefix acts as a placeholder until HUGO assigns an official prefix to these STRs.

Hester M. Wain, Elspeth A. Bruford, Ruth C. Lovering, Michael J. Lush, Mathew W. Wright, and Sue Povey, Guidelines for Human Gene Nomenclature, Appendix 1: Gene Symbol Use in Publicaitions, Genomics Vol 79, Number 4, April 2002, page 469, doi:10.1006/geno.2002.6748, available online at http://www.idealibrary.com, also https://www.genenames.org/files/PMID11944974.pdf

[49] The list of the 111 STRs and their mutation rates are found in: J David Vance, Chapter Chapter 5 Introducing Short Nucleotide Polymorphisms (SNPs) & Chapter 13 The Genetics of STRs and SNPs, The Genealogist Guide to Genetic Testing, 2020

Other sources for information on STRs:

Summary List of Y Chromosome STR Loci and Available Fact Sheets, STRBase (SRD-1300,  National Institute of Standards and Technology, U.S. Department of Commerce, Last Updated: 06/29/2009   https://strbase.nist.gov//ystr_fact.htm

Y STR Positions along Y Chromosome, STRBase (SRD-130),  National Institute of Standards and Technology, U.S. Department of Commerce, https://strbase.nist.gov//ystrpos1.htm

DYS393, STRBase (SRD-130), National Institute of Standards and Technology, last updated 7 Feb 2008, https://strbase.nist.gov//str_y393.htm

YHRD R68, Locus Information on DYS393, https://yhrd.org/details/locus_information/DYS393

[50] J David Vance, Chaper Chapter 5 Introducing Short Nucleotide Polymorphisms (SNPs) & Chapter 13 The Genetics of STRs and SNPs, The Genealogist Guide to Genetic Testing, 2020

[51] J David Vance, The Genealogist Guide to Genetic Testing, 2020, self published book. 

The book represents an expanded version of the information in videos below and is available in book form (Kindle and printed versions) at https://www.amazon.com/Genealogists-G…

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 1, 10 Oct 2019, https://youtu.be/RqSN1A44lYU

Part 1 of a 3-part introduction series to Y-DNA for genealogists. This first video focuses on “Why?” use Y-DNA for genealogy – what benefits does it offer and why should genealogists consider using Y-DNA as part of their research?

A PDF of the slides used in this video is available at https://drive.google.com/open?id=14xA… A readable transcript of the narration in the video (for those who prefer to read than listen) is available at https://drive.google.com/open?id=1CdU…

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 2, 3 Oct 2019 https://www.youtube.com/watch?v=mhBYXD7XufI&t=355s

Part 2 of a 3-part introduction series to Y-DNA for genealogists. This second video focuses on “What?” for Y-DNA for genealogy – what are STRs and SNPs, what is genetic distance, what is the haplotree, and other related questions

A PDF of the slides used in this video is available at https://drive.google.com/open?id=1vS2… A readable transcript of the narration in the video (for those who prefer to read than listen) is available at https://drive.google.com/open?id=1dCb…

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 3, 10 Oct 2019  https://www.youtube.com/watch?v=03hRXVg9i1k&t=4s

Part 3 of a 3-part introduction series to Y-DNA for genealogists. This third video focuses on “How?” for Y-DNA for genealogy – how do I use the information provided by Y-DNA tests to advance my genealogy and/or my lineages?

A PDF of the slides used in this video is available at https://drive.google.com/open?id=1HPP…A readable transcript of the narration in the video (for those who prefer to read than listen) is available at https://drive.google.com/open?id=1-IL…

[52] Ibid

[53]  Rob Spencer, STR Clades, Tracking Back a website for genetic genealogy tools, experimentation, and discussion, http://scaledinnovation.com/gg/gg.html?rr=strclades

[54] J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 1, 10 Oct 2019, https://youtu.be/RqSN1A44lYU

Part 1 of a 3-part introduction series to Y-DNA for genealogists. This first video focuses on “Why?” use Y-DNA for genealogy – what benefits does it offer and why should genealogists consider using Y-DNA as part of their research?

Rob Spencer, Why use STR data and not SNP data?, Tracking Back a website for genetic genealogy tools, experimentation, and discussion, http://scaledinnovation.com/gg/gg.html?rr=whystr

[55] Much of this discussion on using STRs and SNPs is from from J. David Vance. In addition to his book, he has three YouTube presentations that provide a direct and comprehensive treatment of genetic genealogy, the strategy of Y-DNA testing, and the basic concepts of the field. 

J David Vance, The Genealogist Guide to Genetic Testing, 2020, self published book. 

The book represents an expanded version of the information in videos below and is available in book form (Kindle and printed versions) at https://www.amazon.com/Genealogists-G…

A PDF of the slides used in this video is available at https://drive.google.com/open?id=14xA… A readable transcript of the narration in the video (for those who prefer to read than listen) is available at https://drive.google.com/open?id=1CdU…

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 2, 3 Oct 2019 https://www.youtube.com/watch?v=mhBYXD7XufI&t=355s

Part 2 of a 3-part introduction series to Y-DNA for genealogists. This second video focuses on “What?” for Y-DNA for genealogy – what are STRs and SNPs, what is genetic distance, what is the haplotree, and other related questions

A PDF of the slides used in this video is available at https://drive.google.com/open?id=1vS2… A readable transcript of the narration in the video (for those who prefer to read than listen) is available at https://drive.google.com/open?id=1dCb…

J. David Vance, DNA Concepts for Genealogy: Y-DNA Testing Part 3, 10 Oct 2019  https://www.youtube.com/watch?v=03hRXVg9i1k&t=4s

Part 3 of a 3-part introduction series to Y-DNA for genealogists. This third video focuses on “How?” for Y-DNA for genealogy – how do I use the information provided by Y-DNA tests to advance my genealogy and/or my lineages?

A PDF of the slides used in this video is available at https://drive.google.com/open?id=1HPP…A readable transcript of the narration in the video (for those who prefer to read than listen) is available at https://drive.google.com/open?id=1-IL…