In 1885, Xaver, a young Austrian blacksmith, left home to make it big. After finding a new job abroad, Xaver, a gentile, fell in love with Dina, the 17-year-old Catholic-Jewish daughter of his boss. He was subsequently fired. But that was just the beginning of this family drama.
Dina ran away from home to be with Xaver and found lodging and work in the home of Ron, a 30-year-old Jewish factory owner. In 1887, she gave birth to a son, named Renc, believed to be fathered by Ron. Renc received Jewish rituals and was baptized in a Catholic church.
But Dina and Xaver remained together, and after Xaver had achieved some success in his career, the two married in 1889. Xaver acknowledged the then one-and-a-half-year-old Renc as his stepson, and Ron lent support to the family. Xaver and Dina went on to have three more children, including a son named Arles. During World War II, Renc’s full Jewish ancestry was kept a secret, while he and his relations lived in fear of being deported to the concentration camps.
The secret of his paternity was maintained publicly for years, but among the family the true identity of Renc’s father was passed down from generation to generation.
Fast forward to May 2017, when Cordula Haas, a forensic geneticist at the University of Zurich, Switzerland, was approached with an unusual request. Renc and Arles’ descendants wanted to verify that Ron was indeed Renc’s true father. The family offered up cheek swabs from living descendants of Dina, Renc, and Arles for DNA analysis, and—at the prompting of Haas—some postcards that had been sent by Renc and Ron that might hold their DNA in the remnants of the saliva used to paste the stamps.
Solving kinship cases is a common task in forensic genetics, but this case was a little more complex than Haas was used to. For a year and a half, she and her team tried to confirm the story, to no avail. By October 2018, they had thrown in the towel. But then, in March 2020, the family returned, this time with more heirlooms. They had found some more old postcards that had been sent by Arles on a business tour in 1922.
The scientists compared the DNA found under these cards’ stamps with the DNA found on postcards sent by Renc while he was fighting in World War I and on postwar trips. They found common Y chromosomal lineage, which meant that the two brothers shared the same father. After more than a century, the family had an end to their paternity drama: Xaver, not Ron, was Renc’s dad.
With the consent of the family, Haas and her colleagues detailed their investigation in a paper published this month in the journal Forensic Science International. (All the names were changed, at the request of the family.) And while it might seem like no more than an amusing end to a family mystery, extracting centuries-old DNA from artifacts—a licked envelope flap, hair from an old brush—was once considered the Next Big Thing in genetic genealogy. Its promise lies in offering anybody the opportunity to gain precious insights into long-deceased ancestors and loved ones, to look further back into their family tree, and to potentially reunite with existing relatives.