Recently, a 4th-6th cousin on AncestryDNA, uploaded their DNA to GEDmatch.com – and it was pretty much what I expected. My mom and her shared 59cM of DNA across chromosomes 1 to 22. How in the world did I not notice that my mom and this match shared 73cM on the X chromosome!?
Now I have something a bit more promising to go off of – The X chromosome, from my understanding, is only around 200cM long – don’t go quoting me on that. 🙂 So I think 73cM on the X chromosome is kind of a big thing.
I had originally assumed the shared ancestors between my mom and this match were Peter Kunz and Anna Catherine Streider. Her connection to Peter Kunz and Anna Streider is through one of their sons. Seeing as an X chromosome can not pass from a father to son, I think Anna Streider passed this X to her son.
Anna Streider -> Son -> Daughter -> Son -> DNA Match
When a son passes down his X to a daughter, there is no room for recombination because he only has 1 X.. Since this DNA cousin’s ancestry goes in the boy-girl-boy-girl pattern, I think that’s why my mom and her share so much X-DNA.
How this makes a difference in my search…
Peter and Anna had load of kids and I have to look at all of them since I’ve determined that Anna is the X-Donor..A mother passes an X chromosome to both boys and girls. But when I’m looking at one of their son’s I can focus squarely on his daughters since he can’t pass down the X chromosome to his sons. It rules out a good handful of descendants.
So far, I’ve come across a couple of males born in 1949 but none have had the DNA links like I need to confirm a relationship.
I’ll let you know if I come up with anything new from searching like this… but good grief this is one HUGE family.