Friday, February 27, 2015

Switched at Birth: Unraveling a Century-Old Mystery with DNA

The following is a guest post by Alice Plebuch demonstrating the potential of DNA testing. When Alice first contacted me about two and a half years ago with the beginning of this incredible tale, I knew that the answer was just waiting to be discovered one day through genetic genealogy. Many of you may have heard part of her family's story already, but I thought it only made sense for Alice to share it from the beginning through to its completion since it was her DNA test that started the unraveling of this mystery and her persistence that, finally, led to the resolution. (The final piece of evidence just arrived this week and, with it, the confirmation needed by Alice's family to finally share their story.)

Three years ago I blithely took a DNA test at AncestryDNA. At the time, the fact that it was in beta, somewhat alleviated my concern when I first saw my results. I was three quarters Irish with the remainder being a English/Scottish mix, but the test claimed I was half Jewish. It was as if half my ancestry was wrong. The results had to be wrong! I was expecting to see Mc and Mac relatives, but the names were overwhelming Eastern European, Russian, and Jewish. I can assure you, they weren't any of my relatives, or were they?

Alice's Unexpected Ethnicity Estimate

I have six siblings strewn all over the United States. By chance, two brothers visited within days of my receiving the perplexing DNA report. Their reactions ranged from finding the Jewish component mildly interesting, but wrong, to outright ridicule. How could I ever imagine we were anything but Irish, they asked? Nothing makes me take an opposite position faster than being mocked. I defended the test, even as I harbored huge doubts. Looking at the family trees of my matches became a daily endeavor and I wondered, could I really be related to these people?

I called my only sister, Gerry, and shared the disturbing results. Her immediate and intense reaction was that the DNA test was correct. Gerry thought it just felt right. I had conducted some research on genetic testing companies so when Gerry decided to test, I recommended 23andMe where I knew we'd have direct access to our genomes. I also retested at 23andMe.

Waiting on the second round of testing gave me time to imagine incredible scenarios, most notably, "I was adopted" and "Mom had an affair"! Gerry laughingly dismissed those notions by reminding me of how much we all resemble Dad. Everyone in the family has Dad's distinctive eyes and I certainly have his flat feet and massive bones. Nevertheless, it was a real relief when the first thing I saw in my DNA family list was a nephew with the proper relationship. Shortly thereafter, Gerry's results were posted. We were full sisters and both half Ashkenazi! Another brother casually mentioned he also tested at 23andMe. His profile was neither public nor had he even looked at his ancestry composition. We quickly shared genomes and it was three for three.

To be on the safe side, I sent a copy of my genome to Doug McDonald, a retired professor at the University of Illinois, noted for calculating accurate ancestry admixtures. His analysis was quite pointed. "It can't be any clearer. One of your parents is Jewish."

23andMe's Ancestry Composition Feature Shows Fully Jewish Chromosomes for One Parent

Now that the Ashkenazi component was verified, the question of which parent remained. Our prime suspect was Dad. Mom had an extremely well documented family tree, but more importantly, we personally knew many of her huge extended family and they were definitely not Jewish. We had pictures of Mom's family extending back over a hundred years. Dad's parents died while he was young, and kin did not raise him.

So together, my sister and I worked out a plan where we would test first cousins from both sides of the family. Our cousins are considerably older than us and we were concerned they wouldn't be open to DNA testing. We were pleasantly surprised when they eagerly agreed to spit for us. Their one request was that their identities be kept private.

We also asked our brother, Jim, to take a Y-DNA test through National Geographic. His test came back, indicating his genotype is the predominate type in southern Ireland where our grandfather was born. Almost as a footnote, it was mentioned that a small number of Ashkenazi Jews shared the genotype.

23andMe has a facility called Countries of Ancestry that displays areas on a person's chromosomes that are associated with Ashkenazi Jews. Those areas are displayed in blue, the rest in white. Once again, I found myself staring at a computer screen trying to make sense of what I was seeing. I kept flipping back and forth between the chromosomes of Bill, Gerry and myself, when suddenly I had a "Eureka!" moment. Males inherit their X-chromosome exclusively from their mothers while females get one allele from their mother and the other from their father. Blue permeated each and every single chromosome for Gerry and me, but there wasn't a single dot of blue on our Bill's X-chromosome. Dad was Jewish!

Alice's X-chromosomes show Jewish DNA

Bill's X-chromosome shows no Jewish DNA

Armed with the knowledge that the Ashkenazi genes came from Dad, Gerry and I made a friendly bet. I wagered that our paternal cousin would also be Jewish. My sister was just as sure he wouldn't be related to us. She had come to the seemingly ludicrous conclusion that "Dad was switched at birth!"

More waiting provided time to research Dad's parents; after all, they could have been Irish Jews or Jews that assumed Irish persona so they could more easily enter the United States. Now that everything is on the Internet, it was relatively easy to verify that our grandparents came from Irish Catholic families, marrying into other Irish Catholic families, for quite some time. There was no hint that they were anything other than Irish.

It was almost as Loki, the trickster, was having fun with us. One cousin's kit had the correct address on it, but it was delivered it to the wrong address and the person just kept it, unopened. The other cousin's saliva didn't yield sufficient DNA and had to be reprocessed. At last the results arrived. 

Mom's nephew was almost classic 1st cousin match. I went cold when I ran the comparison for Dad's nephew. None of us had any genetic relationship with him, whatsoever. He was as Irish as we were Jewish! I lost the bet with Gerry, but more importantly, was left with the unenviable task of telling our beloved cousin that we weren't genetically related.

The family was stunned. Our brothers were no longer laughing. My sister and I swung into high gear to find our biological grandparents.

The big question was how could Dad become separated from his family. In 1913, most women had home births, but Dad's birth certificate clearly states he was born in a hospital. Even today, with high-tech monitoring, occasionally babies are misidentified. Imagine a hospital that has just started delivering babies and didn't foresee mix-ups, much less DNA. We knew when and where the other baby was born so we turned to The New York City Birth Index, in which we identified thirty male infants born in the Bronx within a day of Dad.

Our untested brothers dutifully spit into test tubes so we'd have a better chance of finding a match. Then, all our genomes were transferred to Family Tree DNA and GedMatch to widen our dragnet. Although Jim already took a Y-DNA test, it only reported on 12 markers; far too few for genealogical purposes. Bill volunteered to take the more expensive, but much more accurate, "111-marker Y-DNA" test at FTDNA. Although Bill had the same genotype as Jim, his matches were with Ashkenazi men of Eastern European ancestry, with the notable exception of an Irish man with our surname! We choose to discount the Irish match as being a NPE after talking with the family. Bill had a single "extremely significant" match that predicts a common ancestor within 4 generations. We were hopeful and dared wonder, "Had we found our father's true surname?" Unfortunately, autosomal DNA tests indicated a more distant relationship.

It was suggested that what we should look for a Jewish baby with a surname similar to ours. In fact, there was a male infant with a very close, but distinctively Jewish, surname. Thanks to a birth announcement in the NY Times we were able to trace the family into the present. DNA testing showed he couldn't be the Irish child. Our hopes for a quick and easy resolution were crushed.

Thus began the tedious work of the next two and a half years. On behalf of the family, Gerry and I sent out over a thousand invitations to share genomes at 23andMe. We also contacted many of our approximately 3,000 DNA cousins (each, for a collective total of 7,000 unique cousins) at FTDNA. The overwhelming majority of DNA cousins never responded, a few hurt our feelings by refusing to even speak to us, but enough accepted to build an excellent search base. A few of our Jewish DNA cousins have become fast friends and marvelous co-researchers.

As more and more match data accumulated, it became obvious to Jim, that the spreadsheets we used were unwieldy. Jim used his skills as a developer to create an iPad application, DNAMatch, which easily and efficiently managed the 300,000 plus overlap segments our large family has generated. Real analysis was finally possible.

Jim's DNAMatch Automated Spreadsheet Feature

We had massive amounts of information on the location and surnames of our DNA cousins and were able to make some predictions. Minsk, Vilna and Ukraine were clearly geographic "hot spots", yet some of our closest matches traced their families to Romania. Many were related to us on both sides of their families. While the majority of our contacts knew their ancestors came from Russia, they weren't sure of the town or even the name of the current country. Ancestral surnames changed at a dizzying pace or they simply didn't exist. I hate to admit I was getting depressed over the probability of finding our grandparents, but...

Dad's Irish nephew has always been supportive of our quest and I provide him with updates. His 23andMe DNA Relatives list doesn't change frequently, so I'd fallen into the habit of checking his matches monthly instead of daily. In the middle of my most current update, rather than report a lack of progress, I stopped and signed on to his profile. OMG! OMG! There, right below his name, was an anonymous woman listed as a second cousin. In my heart-of-hearts, I knew she was the key. With my heart pounding and my hands shaking, I wrote her a personalized invitation, explaining that I managed my cousin’s account. Would she would compare genomes with him to help me solve a 100-year-old mystery concerning my father.

When she accepted, I wrote, “Thank you for responding so quickly. P N [his posted name] is helping me discover who my real grandparents were. Theoretically, we are first cousins, but I found out, through a DNA test that my Irish father is, in fact, fully Ashkenazi Jewish. We tested all our first cousins and he doesn't match my family at all, which is impossible if we were genetic first cousins. Every expert that has looked at the evidence is convinced, as are we, that Dad was accidentally switched at birth with the Irish child.”

Jessica, the young woman, in turn responded, “I was actually expecting to be much more Ashkenazi than I am. My father died when I was very young, but I was always told that both his parents were descended from Eastern European Jews. Through this test I've found that I am only about 2% Ashkenazi and that I am actually Irish, which I had not expected at all. So I'm not really sure what is going on.”

I explained when and where Dad was born and within 20 minutes Jessica wrote to say, “Just glancing quickly through internet records, it looks like my dad's father, Philip, was born on September 24, 1913, so you may well be on to something.” She later confirmed that her grandfather was actually born a day earlier, just like Dad. Her grandfather’s name was on my list of “suspects”, but his surname was misspelled!

It was late at night when we finally emailed our “good nights”. Sleep was impossible, making the wait until morning, and sharing of the joyous news, sheer agony.

We received email photographs of our grandparents the following afternoon. What an incredible feeling it was to look at old snapshots and see those familiar, smiling, faces. There was Dad’s hairline, his nose, his ears, and eyes on his father. Dad’s mother graced him with her marvelous facial bone structure. There is no denying — we’re related.

Alice's parents on their wedding day

Alice's newly discovered biological grandparents Sam and Ida

Alice's father

Our wonderful Jewish DNA cousins constructed our family tree within hours. With a real tree, my closest DNA match at Ancestry found we share the same 2X great grandparents and, today, the DNA test on Jessica’s Jewish grand aunt — my presumed 1st cousin — confirms we ARE indeed first cousins! Dad really was switched at birth!

Matching DNA between Alice and her new
first cousin plus four of Alice's siblings

And now our Irish family is Jewish. Our "Swap Cousins" are Irish and are trying to adjust to this shocking news. We’re all hungry to learn about each other's family and how to intertwine the two families, Irish and Jewish, into one tree.

Despite all our careful planning and matching of cousins, our final success is attributable to a one-in-a-million, unpredicted match. I’m not a particularly religious person, but the inexplicable events that lead us on this remarkable odyssey, and its unexpected and spectacular conclusion, are sure having an effect on my belief system!


  1. Wow. Good work figuring out the mystery. I've downloaded the app.

  2. I am so happy that you were successful in your search. Persistence, and the cooperation of many others, really did pay off.

  3. Good, solid research and persistence, with a wonderful result that wouldn't have been available even a few years ago. Congratulations to all of your family.

  4. Wow! Thank you for posting this fantastic family story.

  5. Wow I love the story and it makes you wonder how many other babies could have been accidentally switched at birth or even on purpose. Thanks so much for sharing such a great story.

  6. Fascinating! I commend your continued searching, and am proud that you were able to learn so much. My sister had hoped for a story like this, but alas, we are 97% white European as we thought!

  7. I've been following your story on Facebook but how amazing to see it all laid out here. Congratulations!

  8. Wowsa! I may need to read this a couple of times to take it all in. What a story!

  9. Happy to finally read the other side of this amazing story!

  10. What a story of persistence and the power of DNA! We are working with a mystery second cousin...I had not thought of this possibility.

  11. What an unbelievable story! It really gave me the chills, even though I'd read Jessica's blog first and knew the ending. Congratulations on solving the mystery, and good luck to all of you involved. (And welcome to the tribe!)

  12. The resolution to your unfolding Plebuch story is enormously exciting! Congratulations for persistent determination to solve this head-scratching mystery. Several of my family members (and I) connect to you and your siblings through DNA, and that makes me feel a personal attachment to this remarkable tale. So far it is evident that we connect through your maternal lineage (and our paternal lineage), yet the suggested kinship is distant enough that we may never identify that common ancestor. Who knows though, the challenge may one day surprise us.

  13. Great writeup! I read Jessica's writeup previously but this is a remarkable story.

    It also makes me wonder how many other switched at birth babies existed, and how many of their descendants may now mistakenly think they have an NPE in their tree.

  14. what a wonderfully amazing story!!!!

  15. I wish there were pics of each switched child with the "wrong" parents, but suppose that is not possible. Great, well-written article.

  16. I wish there were pics of each switched child with the "wrong" parents, but suppose that is not possible. Great, well-written article.

  17. Great, well-written post. I do wish there were pics available of the Irish family too, but suppose that might not be possible

  18. What a fascinating story! Thank you for sharing it. I've included your post in my Noteworthy Reads post for this week:

  19. Amazing story. I checked out the link to DNAMatch wish it was able to be downloaded to my PC or Android

  20. Alice - Great research, impressive!
    Your newly discovered 4th cousin (I think).
    Dennis Zink (Sarasota, Florida)

  21. Thank you for sharing your story. My father was adopted and I know his mother. His father is unknown, so l I have a long journey ahead of me.

  22. Anybody want to help me with my searching my grandfather did a ancestry DNA test as did his brother and they are not related (as op father wasn't) so now I have started the search I don't have money for DNA tests but I'm stubborn and I want to find his family (hopefully brothers or sisters as it's not likely his parents are still alive) before his bad health fails I want him to know them I want to know them anybody want to help?

    1. Hi, sounds intriguing. Please send me an e-mail at

  23. I came across this article because I find myself in a similar situation. I took a DNA test yesterday and got 0% Irish when my mom is supposed to be half Irish from her fully Irish father. She is definitely my mother, and he is definitely her father-the resemblance is extremely strong. So now I'm wondering if something happened with my grandpa at birth as well. He was born in 1910. I want to ask her things, like did your dad look like his siblings, his parents, but I also don't want to destroy her life. I may buy her a test to see what she gets first.