History can help understand DNA ethnicity profiles: an example #dna

Joseph Walder

A non-Jewish friend has great-grandparents who came from Sweden (maternal side) and Germany (paternal side). The latest iteration of her DNA ethnicity profile from Ancestry indicates a Swedish component approaching 75% and a German component of only a few percent. This result seems baffling until one considers an important detail: the German ancestors came from the region of Pomerania, that is, from along the south shore of the Baltic Sea. Pomerania (which with post-1945 borders is now mainly Polish territory) was only incorporated into the Germanic world in about the 15th century. The population along the south shore of the Baltic at that time was a mixture of Slavs, Balts, Finnic peoples, and Swedes--and indeed the friend's Ancestry DNA profile indicates greater Slavic, Baltic and Finnic contributions than Germanic. A plausible interpretation is that her German great-grandparents were the descendants of non-Germanic people who assimilated to German culture and language several centuries ago.

To the extent that Ashkenazi Jews intermarried with and assimilated non-Jews, the surprises that some Jews find in their DNA ethnicity profiles are, well, unsurprising.

Populations have always mixed with each other. Geography, culture and language cannot be simply superposed on one another. History can provide very useful guidelines for interpreting DNA profiles.

Joseph Walder
Portland, Oregon

Linda Z

Hi Joseph,
  While you state much more eloquently and your post addresses a certain locale of assimilation I couldn't agree with you more regarding assimilation. I have met so many peeps during my travels along with moving from one shul to another and found that those who boast the most in their heritage either know already and refuse to accept or are finding out that they are not 100% Jewish through their recent testing. Yet we continue to hear an occasional slant here or there. 

   A dear friend from shul here where I live told me years ago  that she had Christian family in her tree and had to think of them around the holidays. I was astonished as she was a leader in the shul but it truly did lift my spirits a little to know I wasn't the only one and began to ponder how many more were the same. Certainly those of educational background regarding geographical history know this but not all of us have such knowledge. Your tidbit of information is so important to those of us searching, reading and learning here so I thank you for your post. Took me forever to find a certain Jewish relative but using this site with much geographical information helped me to determine that one and find her. And yes there are many more Jewish people than like to admit that they have more non-Jew background DNA than they thought. Even with records passed down one can find assimilation.

   Regardless, DNA and genetic behavior is passed down the generations just the same. Wonderful topic to study. Think in terms of a person getting a heart transplant from a donor who suddenly finds they love to play piano although had never touched one before. Same with our Jewish DNA found among those of later generations from those ancestors who assimilated. Grands, even down to the 3rd and 4th generation have a deep sense of knowing they are Jewish without having to be told or having privy to Jewish culture in their lifetimes. Some spending a lifetime searching for that Jewish connection. I think of Jenny Milgrom whom all know here who knew she was Jewish although she was raised Catholic. But many more today share these same sentiments. While records might be worth more than DNA testing it is still true that genetics in the absence of records don't "lie". 

   I read here that records passed down are the most reliable .Unfortunately many here do not have those precious records as in my case all of my immediate and extended family who would have had such records have passed and those records either discarded or passed to some in the family who had no inkling of a clue. So my searching here is new and I feel like a fish out of water as I read of how advanced so many are in their searches. I have been a member here for awhile but have learned an enormous amount of knowledge "just by reading" thanks to the kindness of Abraham who created this site and as well to Gary Mokotof and Sallyann Amdur Sack for their seemingly tireless efforts in their regard toward helping Jews find their relatives. I finally got the courage to post my first post here just a week ago and even then had to redo as I didn't fill it out right. Now that I know I am going to continue to read and post. In my older years I realize how much I have missed not knowing there was so much information available to help those of us searching. So again thank you for valuable information that are tidbits of info helping those of us searching. Incidentally just by reading on this site I found out from a reply to my quest that Jews in fact did name their children Christian names. I was overlooking them in my tree. 

Sharona Zaret (shortened from Zaretsky)


Adam Cherson

This is a situation that could be unraveled using genography. When in doubt: go deep!

Adam Cherson,,,20,0,0,0::Created,,%23dna,20,2,0,76689650,ct=1&ct=1