Genetic genealogy debuted more than 20 years ago as a pastime for ancestry enthusiasts. The customer sent a saliva sample to a company like FamilyTreeDNA and could then log in to a website showing how closely their genetic markers matched with those of other people — long-lost relatives — in the company’s databases.
Margaret Press, a software developer and mystery writer, had used the method for years to help adoptees find their biological parents. In 2017, while reading a novel based on an unsolved murder, she realized that her skills might be equally useful to law enforcement.
She co-founded a nonprofit, called the DNA Doe Project, to try to match unidentified remains with genetic profiles that had been uploaded to an open-source genealogy database called GEDMatch.
On April 10, 2018, the DNA Doe Project announced that it had used this method to positively identify a 21-year-old woman, previously known only as the “Buckskin Girl,” who had been found strangled in Ohio in 1981; it was the first time the public learned about a cold case solved with genetic genealogy.
That case made headlines for weeks, and “the floodgates opened,” Dr. Press said. Investigators across the country were eager to try the technique on their own cold cases, and an industry sprang up to help.