When you're Ashkenazi Jewish, yDNA tests are often not as useful as they are for Western Europeans--or even Sephardic Jews. yDNA is passed father to son, so it tracks with surnames; therefore a Williams or a McDonald male takes a yDNA test would expect many matches with surnames of Williams or McDonald. But most Ashkenazic Jews haven't had surnames for longer than 200 years (some even less), so generally a yDNA test on an Ashkenazic male yields a match list of multiple completely unrelated surnames.
I've tested males in several of my surname lines, and no one had any matches with their own or similar surnames (other than known relatives). But then a few months back, another Diamond popped up on my father's yDNA kit.
As I blogged at the time, there were other intriguing aspects. The match didn't know his grandparents' names, but he knew that his father was Hillel Diamond. Hillel Diamond was also the name of my great-great grandfather. His gentleman's father was born just around when my Hillel would have died, so I thought that perhaps he was named for my Hillel--and that would imply that we were relatively close cousins.
I did a lot of research on this Diamond family, who had been in America for nearly half a century before my own Diamonds.
My conjecture was that the American Hillel Diamond's father (Samuel) was a brother of my great-great grandfather. They would have been around the same age, and it would make sense for him to name his youngest child after a recently-deceased brother. And since I have Samuel's death certificate with his parents' names, I would be able to get back another generation for my own family.
After several months ofannoying convincing this gentleman to add a FamilyFinder autosomal test onto his kit, he finally agreed to this Thanksgiving weekend. Less than two weeks later, the results arrived. And here's how he matches my family members who have tested: not well.
He shares absolutely no DNA with my father. He shares small amounts with my father's tested siblings (largest segments 10cM and 8cM). He shares small bits with my father's second cousin Dan (largest segment 10cM). He shares no DNA with my father's first cousin Berly, a little with Berly's sister Paula (largest segment 8cM). My father's first cousin Stephan does share a bit more--his largest segment shared is 17cM--but that is the largest segment over 5cM.
If this gentleman were related as I had expected, he would be a third cousin to this generation of my father's testers. So while it is possible that he actually is a third cousin, the fact that none of them have good matches imply to me that he isn't at all closely related. This distribution of largest segments doesn't look any different than I'd expect in a random Ashkenazi tester.
So what yDNA has given, autosomal DNA has taken away.
Happy Chanukah!
Note: I'm on Twitter. Follow me (@larasgenealogy).
I've tested males in several of my surname lines, and no one had any matches with their own or similar surnames (other than known relatives). But then a few months back, another Diamond popped up on my father's yDNA kit.
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| The first match is Uncle Leibish's grandson (my father's second cousin). The second is this new match |
As I blogged at the time, there were other intriguing aspects. The match didn't know his grandparents' names, but he knew that his father was Hillel Diamond. Hillel Diamond was also the name of my great-great grandfather. His gentleman's father was born just around when my Hillel would have died, so I thought that perhaps he was named for my Hillel--and that would imply that we were relatively close cousins.
I did a lot of research on this Diamond family, who had been in America for nearly half a century before my own Diamonds.
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| The Match's Grandfather's Death Certificate |
After several months of
He shares absolutely no DNA with my father. He shares small amounts with my father's tested siblings (largest segments 10cM and 8cM). He shares small bits with my father's second cousin Dan (largest segment 10cM). He shares no DNA with my father's first cousin Berly, a little with Berly's sister Paula (largest segment 8cM). My father's first cousin Stephan does share a bit more--his largest segment shared is 17cM--but that is the largest segment over 5cM.
If this gentleman were related as I had expected, he would be a third cousin to this generation of my father's testers. So while it is possible that he actually is a third cousin, the fact that none of them have good matches imply to me that he isn't at all closely related. This distribution of largest segments doesn't look any different than I'd expect in a random Ashkenazi tester.
So what yDNA has given, autosomal DNA has taken away.
Happy Chanukah!
Note: I'm on Twitter. Follow me (@larasgenealogy).
I wonder how well the Y-DNA match would hold up if he upgraded to 111 markers?
ReplyDeleteIt took him nearly 6 months to do the FamilyFinder. I don't know that 111 is in the cards!
DeleteWell, there is always the BigY, which currently will give you the 111 as well.......get the two BigY tests and see what kind of match you get. There are coupons for this week for the BigY (usually $50)....
ReplyDeleteIt took 6 months to convinced him to do the FamilyFinder....
DeleteTake a look at the time predictor (TiP) model prediction at the 70-80% probability level. That should give you a pretty good idea of when their common ancestor lived. Based on a 4-step difference at 37 STR markers, it seems likely that he lived during the pre-Jewish surname era, but if the 4-step difference is due to fast mutating markers on the same palidrome, it is possible that the common ancestor lived during the post surname era.
ReplyDeleteHe actually is predicted to be slightly closer than my dad's known second cousin!
DeleteYou didn't specify the genetic distance, what was it?
ReplyDeleteIt's in the image above--distance 4 (with my father's known second cousin at 3).
DeleteI have stopped even checking the Y matches and the mtDNA matches. (I barely check the autosomal.) I feel your frustration. Happy Hanukkah! There is always the possibility of a miracle. :)
ReplyDeleteThis might actually be a situation where it is NOT that the autosomal DNA couldn't have taken it away but that it could just get the job done and reach back to the 3X-grandfather. A Big Y out of the two matches would probably get the job done and give you final answer.
ReplyDeleteIt's possible, but the statistics of this many people not matching are extremely low. Unfortunately I don't know that I'd be able to convince the other gentleman to do the Big-Y; it took months to get him to add a FamilyFinder!
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