Updated: Jul 2, 2019
Y-DNA is contained within the 23rd chromosome pair and is only inherited by males patrilineally or father to son, father to son, etc. Although it will only return matches through this particular line it has the advantage of easily going beyond the 5 – 6 generation barrier that the more common autosomal DNA tests experience (Ancestry DNA, 23andMe, FTDNA Family Finder, etc.). In my efforts to accurately characterize and estimate the Y chromosome of my family's brickwall ancestor Charles Daugherty I started off by genealogically investigating all of his descendants to find prospective testers. Charles and his wife Elizabeth were the parents of 3 sons and 1 daughter from the years 1799 – 1806 (see Figure 1). My Y-DNA exploration began with a Y111 STR test for myself (8/22/2016) followed later by a Big Y test (completed in early 2017). I descend from the oldest son George Daugherty (1799 – 1877)* and am 7 generations below the brickwall ancestor Charles. This generational distance leaves some room for my Y chromosome to mutate compared to what Charles' Y would have been. *Note: Ancestor hyperlinks lead to detailed genealogical profiles for the ancestors at the free to register TNG (The Next Generation of Genealogy Sitebuilding) based Association of Ó Dochartaigh's Genealogy and DNA Trees website. The goals of this exploration of Y-DNA differences between descendants of the brickwall Charles is to accurately estimate what his Y-DNA might have looked like within him which allows him to be more accurately placed within the greater group of Ó Dochartaigh Y-DNA testers.
My first willing tester was a descendant of Charles and Elizabeth's youngest son, John Dougherty (1806 – 1879), who is the last known carrier of John Dougherty's Y chromosome. With his results posted on 6/24/2018 I now had a new Y111 match with a genetic distance (GD) of 4. Compared to the primary clade of Ó Dochartaigh testers, this new tester's Y chromosome did not mutate much in relation to the "nearest neighbors", or those testers that most closely match our family in an unknown way beyond Charles Daugherty. This seems more likely given that this tester's generational distance to Charles is only 5 generations where mine is 7....so more opportunity for mutations in my line of 7 generations. During Family Tree DNA's 2018 Holiday Sale myself and a female descendant of Charles' middle son also named Charles Daugherty (1801 – 1880) was able to recruit a tester descended from this middle son. This middle son has a vast number of living male Daugherty descendants who have inherited his Y chromosome. His Y111 results recently completed (2/8/2019) and is a GD of 7 to me and 3 to the descendant of John Dougherty. This descendant of the middle son is a 5th Cousin 1 Removed (5C1R) to me and a 4C1R to the descendant of John Dougherty (see Figure 1 for relationships). So now there are 3 – Y111 STR tested descendants of the brickwall Charles Daugherty, one from each of his sons. They currently reside on rows #165-167 within the public Group 1 Ó Dochartaigh testers (subject to change as more testers are recruited to Group 1). Using David Vance's SAPP (Still Another Phylogeny Program) a Mutation History Tree (MHT) was created based on known mutation rates of STR markers, known SNPs between testers and known genealogy between various testers (see Figure 2). STR mutations are in bold black lettering to the upper right of Nodes and testers.
As a result of this exploration we see that the John Dougherty descendant tester (836596) has likely had no mutations since the brickwall Charles Daugherty based on SAPP's estimates. It is more parsimonious (conservative or likely) that myself (B121647) and the descendant of Charles Daugherty (1801 – 1880) (798860) have undergone more STR mutations down our respective lines. To further explore George Daugherty (1799 – 1877) descendants, I recruited a 2C2R tester (YS19043) descended from Samuel Daugherty (1863 – 1941), brother to my 2nd great grandfather Emery D. Daugherty (1872 – 1957), to test at YSEQ for the specific STRs that mutated between the brickwall Charles Daugherty (Node #274) down to me (B121647):
This exploration will characterize the change in STR markers since the brickwall Charles Daugherty's grandson John W. Daugherty (1823 – 1883) to both me (B121647) and tester YS19043; and will allow me to know if the mutations in these markers likely occurred between brickwall Charles and John W. Daugherty or between John W. Daugherty and the two descendant testers. STR makers are being individually evaluated at YSEQ for $9. Additionally, as a result of the Big Y test on myself, I am also evaluating tester YS19043 for two out of the three novel variants found in my results. Novel variants are Y-DNA SNPs that mutated in my line after the unknown ancestor shared with testers N90417, 29142 and 722353 represented by SNP FGC52373 (see Node #299 in Figure 2, estimated to have existed around 1650 A.D.). Similar to the STR exploration of descendants to John W. Daugherty above, exploring the 2 remaining novel variants will allow me to determine if they occurred between the brickwall Charles and his grandson John W. Daugherty (1823 – 1883), or between John W. Daugherty and me. The reason I am evaluating this tester for only two of the three novel variants found within me is because I discovered that one of my novel variants formed in me and is not found within my full male sibling. Exploring the Y-DNA characteristics found within and since John W. Daugherty does not help to more accurately estimate the brickwall Charles' Y chromosome, it simply is curiosity on determining when and within whom my personal STR and SNP mutations occurred. Stay tuned for further updates....