I haven't blogged in a while, so I decided to create a quick blurb on Family Tree DNA's new Match Time Tree, which is part of their FamilyTreeDNA Discover toolkit. A quick primer on DISCOVER: it is a platform available to anyone to view certain components publicly; however, the data it utilizes comes purely from Big Y (500/700) test takers.
Discover Features:
- Haplogroup Story
- Country Frequency
- Notable Connections
- Migration Map
- Globetrekker
- Ancient Connections
- Time Tree
- Match Time Tree
- Ancestral Path
- Suggested Projects
- Scientific Details
- Compare
- Classic Tree
The feature I want to discuss briefly is the new Match Time Tree. This feature is only viewable via the dashboard of a test taker who has completed a Big Y-level Y-DNA test. Otherwise, it will only show a video preview to those who haven't taken the test, encouraging them to upgrade. You can read FTDNA's blog on the new feature HERE.
Although this tool is only available to Big Y testers, it does present their Y-37, Y-67, Y-111, and Big Y matches. FTDNA has implemented a 'Share Mode' that anonymizes the first names of the matches for sharing and presentation purposes. For Group 1 and 2 Ó Dochartaigh Testers (those who descend from the R1b-M222 haplogroup), the tool starts at a Y-SNP R-Z2959—far above these test takers.
This isn't the most helpful view since the unknown ancient ancestor represented by the Y-SNP R-Z2959 lived around ~3 BCE. So, I click on 'Your Branch' at the top of the chart to drill down to my specific lineage. To fit more matches in the view, I reduce the 'Vertical Spacing' to its minimum.
At the bottom of Figure 2, there are two testers belonging to R-BY18291. The first is myself, and the one below me is my father. I've since determined that this Y-SNP mutation, R-BY18291, formed in my father and is only contained within his, my brother's, and my Y chromosomes—it is not present in my first cousin, who branches off above us at R-A24483.
Let us take a look on what happens if I click on my closest match sharing R-BY18291 Y-SNP with me, which is again my Father's Big Y test kit (Figure 3).
When I click on my first cousin, son to one of my father's younger brothers, I'm presented with the display in Figure 4.
Figure 4 shows an estimated Time to Most Recent Common Ancestor (TMRCA) between oneself and their match. In this case, it states that my first cousin and I shared a TMRCA around 1861 CE. I know our shared grandfather was actually born in 1929, but these age estimates are based on various statistical techniques that leverage Y-SNP and Y-STR mutations to estimate a TMRCA and provide a 95% confidence interval (CI) around that estimate. In this case, the CI is 1735-1943 CE.
The reason it cannot be more accurate is that there's only a probability that a new Y-SNP formation or Y-STR change will occur during a Y-DNA transmission event (i.e., the passing of the Y chromosome from father to son). The Big Y 700 examines roughly 18-20 million base pairs of the potential ~60 million base pairs that human males have. There is a possibility of one day having affordable sequencing technology that can access all 60 million base pairs. A recent pre-print study, posted in August 2024, examined four generations of men at this level and found an average of 12.4 de novo Y chromosome events per generation. So, the data may exist to one day refine these age estimates down to a generational level.
Returning to my example, the R-A24483 is a Y-SNP contained in my late grandfather. It may have formed in him, his father John P. Daugherty (1902-1994), or his father Emery D. Daugherty (1872-1957). However, it was not in Emery's father, John W. Daugherty (1823-1883), because it is not present in my Big Y-tested second cousin twice removed (2C2R). If my 2C2R had A24483 within his Y chromosome, this would indicate that our common ancestor, from whom we branched away, would have it as well.
Let us click on my 2C2R to bring up the details window between us (Figure 5).
Again, the 95% CI does capture the birthdate of our common ancestor, John W. Daugherty (1823-1883), but the mean TMRCA of 1780 is about 40 years too early. In my own Big Y exploration of my family, at each possible level from my fifth great-grandfather, Charles Daugherty (b. bef. 1779 Ireland?, d. 1808 Cape Girardeau, Louisiana Territory), I often find that FTDNA's advanced TMRCA estimates are somewhat earlier than actual known dates.
Moving further up to matches known to have branched away another generation back on my lineage, we have a fourth cousin once removed (4C1R) who shares my fourth great-grandfather, George Daugherty (c.1799-1877), the oldest son of my immigrant ancestor, Charles Daugherty. This 4C1R is one generation above me (at the same generational level as my father), making George Daugherty his third great-grandfather. However, there were no Y-SNP mutations that formed within George that my closer family shares with my 4C1R (Figure 6).
Back further yet, to the limits of my known genealogy, we have two cousins who were kind enough to take Big Y 700 tests for me: a fourth cousin twice removed (4C2R) and a fifth cousin once removed (5C1R) (Figure 7). The 4C2R, Charles R. Dougherty (1931-2022), is two generations above me relative to our shared common ancestor and brick wall, Charles Daugherty, and descends from Charles’s third and youngest son, Lt. Gov. John Dougherty (1806-1879). The 5C1R is one generation higher than me, descending from the middle son, Charles Daugherty (1801-1880). These two distant cousins, along with all the aforementioned relatives above, contain Y126341, signifying that our shared common ancestor and immigrant, Charles Daugherty, carried this mutation.
Beyond this, there are matches with whom we do not yet know our genealogical connections. There are three DOHERTY men (Figure 8), two of whom are brothers sharing FGC52368, and another who branched away from everyone in this subclade at FGC52373, with an estimated date of 1607—though it may be closer given the track record of these statistical age estimations.
The benefit of this view is to develop knowledge of geographical regions for the reported Earliest Known Ancestors (EKAs) of nearby matches. For example, the two Big Y-tested brothers who share FGC52368 report their EKA as having been born around 1779 in Donegal, Ireland—which is already more information than I know regarding my EKA, Charles Daugherty. Similarly, the match sharing FGC52373 with the two brothers and my known family group reports their EKA as having been born in 1864 in Buncrana, Donegal, Ireland.
As more testers opt into this more advanced level of testing, it can help further refine age estimations and develop geographical hotspots where our shared common ancestors may have resided. For those interested in examining their Y-DNA connections for their Doherty men are encouraged to test at Family Tree DNA during one of their sale periods (one currently happening until August 31, 2024), which they have frequently throughout the year. The next will be Black Friday, but the prices are usually discounted to the same level regardless of when the sale period is. Any questions or comments feel free to reach me: Dr. Zack Daugherty zack.dohertysurname@gmail.com Volunteer Ó Dochartaigh Y-DNA Project Administrator
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