Finding New Cousins With DNA Evidence
I have always had a fondness for facts. I was baffled in 2006 when a new doctor first told me about “evidence based” medicine; I had previously assumed that all medical practice would be based on evidence. One of the graduate courses I took while studying information security computer science was in “Formal Methods” using mathematics and logic to evaluate the reliability and robustness of a design and form conclusions. I like facts.
In the past, and through most of the entries in this blog, family history decisions were based on the multidisciplinary benchmark of a “preponderance of evidence.” If multiple reports support a cogent narrative, then they are worth repeating. If there are discrepancies, they are worth investigating. Often, by examining different sources, things can make sense. [1]
DNA results are but one tool in the family researcher’s toolkit, but it is undoubtedly evidence based!
In early 2018, I know almost two dozen people with whom I match with AncestryDNA, all descendants of my ancestors who immigrated to the United States either from

Poland marked with author’s ancestral locations
- Marienwerder, West Prussia, now Kujawsko-Pomorskie in north-central Poland, where my father’s grandparents and father were born, or
- Radom, specifically the Sandomierz area of Świętokrzyskie, historically part of the Małopolska (Lesser Poland) region, where my mother’s parents and grandparents were born.
Most of my known DNA matches are close family, first cousins, second cousins, or third cousins, sometimes removed by a generation or two. Since the estimate of relationships is based on the identified amount of DNA we share, a handful of matches are listed by Ancestry as fourth cousins, even though we are second or third cousins in our genealogical trees.
Since DNA can occasionally reveal links that were unsuspected, it has also brought up some surprises.
For example, I knew my grandfather Antoni Maciejewski had two brothers, Konstanty and Ludwik. I knew that their children, my father’s cousins, had grown out of touch. I had heard stories about the rest of the family. I was delighted when I found a family tree online, and even more so in 2016 when my previously unknown second cousin coordinated a mini family reunion in Buffalo, New York, with several of Ludwik Maciejewski/Louis Warner‘s descendants. Some of us confirmed our genetic connection with DNA evidence.
I was contacted by a gentleman from Ontario when we matched on FamilyTreeDNA. Although we both had Szczepański/Szczepanowski names in our family trees, we found that our Szczepański forebears came from different areas. However, we could trace several of our lines to Świętokrzyskie. His experience encouraged me to continue researching Polish records. Although we never identified a most recent common ancestor (MRCA), we were able to ascertain that we both had Zybała, Bokwa, and Sad(owa) ancestors from Koprzywnica and the villages surrounding it.
Another genetic connection was made with a Canadian woman after we had connections on AncestryDNA, FamilyTreeDNA, and GEDmatch. She knew she had been adopted, and her birth parentage had become a concern when one of her children was born with a genetic heart condition. She knew the names of her birth parents, and began cold-calling from a phone book people with her birth mother’s last name until she found a family with similar stories. With additional information, her daughter was successfully treated, and her son’s risk was confirmed for proper treatment. Although we never discovered a most recent common ancestor (MRCA), we were able to ascertain that her father’s parents, named Drach and Wieczorek, were from the villages of Świniary and Suchowola near Koprzywnica.
I heard from a DNA cousin with a Kasprzyk ancestor who had immigrated through Canada to Detroit and then to Buffalo from “Poland Oporto [sic] Russia.” We exchanged newspaper clippings and he shared his findings of a researcher in Poland of his ancestors near Opatów in Świętokrzyskie.
Several second cousins and I were contacted by an AncestryDNA match who had been adopted as a baby. She knew her mother had been Polish, and asked her DNA matches if we could help in her search for her birth parents. I was able to share information about our likely ancestors from West Prussia, and their descendants who had immigrated to America, even if I could not give her specific information about her birth circumstances. They were clues, she said, and helped her pursue her search.
Another genetic match had posted a family tree with entirely different people living in the same town as several of my relatives. There is probably a story there.
I had more in common with one match on FamilyTreeDNA and GEDmatch than just our DNA. Although we were born elsewhere in different decades, we were both Cornell University graduates living in Rhode Island. We both have ancestors who lived in Prussia in the 1800s, although some of his Jablonowski ancestors moved to Höntrop, near Bochum, Germany, before immigrating to the United States.
Because two Polish siblings that I matched on FamilyTreeDNA and GEDmatch were also matches for one of my first cousins one generation removed, I had originally thought we were connected through my father’s family. However, they were from the Świętokrzyskie area, where my mother’s family had lived! It baffled me, until I realized that our genetic connection may be through both his parents, with his father my first cousin on my father’s side, and his mother a distant relation of my mother’s family. That also explains some other anomalies in our results. Even though his mother does not appear to be a DNA match to me, some of her matches are also matches to me, possibly through a long ago ancestor.
Chicago was a common destination for immigrants from Polish lands, so I have found some DNA (estimated) 4th cousins whose ancestors landed in Chicago. They identified their ancestors as Kalinowski or Kaniecki, from Prussia. Although it has been difficult to identify specifically our most recent common ancestors (MRCA), in several instances we were able to identify our common ancestral villages and actually find their ancestors’ baptism and marriage records in Szembruk and nearby places in West Prussia.
I am intrigued with two recent AncestryDNA matches from Long Island with ties back to Buffalo, New York. There is definitely a link, and I am looking forward to learning more about how to evaluate it when I attend the Genealogical Research Institute of Pittsburgh’s course in Practical Genetic Genealogy with Blaine Bettinger at Daemen College in Amherst, New York, this summer.
DNA can confirm genetic relationships you’ve identified through research, find new connections, or cast doubt on identified ancestry. This has all happened in my experience with DNA testing. I have reached out to many DNA matches, and although not all have responded, I am curious about our common heritage. My grandson says we are all related some way. It’s interesting to try to discover how, at least for our closer relations.
[1] Not all evidence is created equal. Professional genealogists apply five criteria in their “Genealogical Proof Standard”:
- a reasonably exhaustive search
- complete and accurate source citations
- analysis and correlation of the collected information
- resolution of any conflicting evidence
- a soundly reasoned, coherently written conclusion