After more than a century of maintaining a family secret, the descendants of Renc decided they wanted to know the truth. Was he fathered by Ron, the Jewish factory owner whom mom Dina worked for when she gave birth in 1887? Or was his true father Xaver, who had been in love with Dina at the time and in 1889 married her, a union that produced three children? Renc was raised as Xaver's son, with Ron providing support, and his Jewish ancestry was carefully concealed during WWII. In 2017, descendants of Renc and Xaver wanted to confirm Renc's paternity, and went to Swiss forensic geneticist Cordula Haas, who requested items that could facilitate that request: not just cheek swabs from modern descendants, but family postcards mailed by Renc and Ron that might have DNA preserved on the licked underside of the stamp.
The postcards ended up not being enough to go on, but in 2020 the family ponied up some more—these sent by Arles, one of the children Xaver and Dina had together. "They found common Y chromosomal lineage," writes Grace Browne in the lengthy piece for Wired, meaning the two men shared a father: Xaver. Browne uses that fascinating story as a jumping-off point from which to explore the increase in companies that offer commercial artifact DNA testing, although she describes the growth of that industry as a "slow burn" due to the expense and the potential that those heirlooms you want tested could be destroyed in the process. It also raises more questions about the privacy owed to those who came before us, something she illustrates with an interesting anecdote about a DNA-related look at King Albert I's mysterious 1934 death. (Read the full story here.)