Sunday, December 9, 2012

Establishing Ashkenazi Connections

In my last post I mentioned that with the new Ancestry Composition you can interactively highlight certain populations in your chromosome by clicking on the group. I provided one with an Ashkenazi separation for myself and a Sub-Sarahan African separation for my grandfather. I want to chat a bit more about the Ashkenazi group and how I've been able to use those chunks of DNA.

When you glance across my DNA, the Ashkenazi chunks only appear three times in "Standard Estimate". The pieces appear on Chromosome 1, Chromosome 4 and Chromosome 9, and with "Speculative Estimate" I receive another piece on Chromosome 7 and a tiny sliver on Chromosome 11. The cool thing about having multiply people tested from my family is that I can rule out who did or didn't give me some of these genes. The two Chromosomes I want to focus on are Chromosome 1 and Chromosome 4. Both of these Ashkenazi genes on those chromosomes I received through my mother and from her father exclusively.
Ashkenazi Connection on Chromosome 1
Here you can see various Chromosome 1 pieces from different people. The first is myself, the second my mother, the third my mother's brother, and the fourth my mother's father. The last entire blue Chromosome 1 is from my Jewish cousin who as you see when compared to myself, my mother and grandfather match us on the same segment. You can also see that I've circled the piece of Ashkenazi gene I received on my Chromosome 1 from my mother and she in turn received it from her father. What's so cool so that this piece of DNA was passed down without really changing, you can see my uncle even received the same piece of DNA on his first Chromosome. Now I want to look at Chromosome 4 where I match a cousin through Ancestry Finder but doesn't have a public account.
Ashkenazi Connection on Chromosome 4 
Here I decided to show it a bit differently by organizing the bars vertically and creating a rectangle horizontally where the Ashkenazi piece is. You can see that my piece of Ashkenazi is a bit longer than my mother's or even grandfather's yet we all inherited that piece on the same spot on Chromosome 4. 

Now, the only thing is trying to figure out how I got that Ashkenazi gene on those Chromosomes. My grandfather's paternal Haplogroup is J1 and my uncle has J1e (for whatever reason, my uncle was placed under J1e) which is found in significant frequencies across the Middle East, being the most frequent in the Arabian peninsula as well as parts of the Caucasus, Sudan and the Horn of Africa. So this Ashkenazi piece could very well be from the male ancestor who passed down the J1 Haplogroup to the Correas. (My maternal male ancestor is Correa but could be something else further back before Spanish surname conventions were adopted. Also I'm not sure whether my family is connected to Antonio de los Reyes Correa from Arecibo, Puerto Rico since my Correa family is located on the South-Eastern part of the island). I have a 4th cousin on 23andme who shares confirmed Correa ancestry with me. When I search her Chromosome 1 or 4 for Ashkenazi ancestry she appears to not have received any on those specific chromosomes, not even on the Speculative level- this could mean two things. It could mean that this piece of Ashkenazi DNA was inherited through the Correa J1 ancestor but wasn't inherited by her. Or it could mean that it came from another family line which she does not connect with. It would take testing other Correa members and people along my maternal paternal family to figure out where these Ashkenazi links come from. 

Also, are they Spanish Inquisition Jewish roots which were passed down to my family or could it be from an actual Eastern European ancestor? These Jewish cousins have ancestry from Germany, Poland, Austria and Lithuania so who knows for sure what the history behind my Ashkenazi pieces are. Hopefully one day I'll be able to look at the Jewish genes and say "You see those pieces of DNA, they came from So-and-so in our family". 

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