The remains of Catoctin Furnace in Maryland as seen in 2020. Researchers have now analyzed the DNA of enslaved and free Black workers there, connecting them to nearly 42,000 living relatives. Katherine Frey/The Washington Post via Getty Images hide caption
Many at-home DNA ancestry testing kits require participants to mail in a sample of saliva. Cayce Clifford/Bloomberg via Getty Images hide caption
An image of Ow Luen from his file, originally held at the USCIS, now available at the National Archives. Grant Din/National Archives hide caption
Sen. Elizabeth Warren, D-Mass., released a DNA analysis to clarify questions about her Native American heritage, something President Trump commonly mocks. Warren is considering a 2020 presidential bid. Tasos Katopodis/Getty Images hide caption
DNA sleuthing helped identify Joseph James DeAngelo, the suspected East Area Rapist, who was arraigned in a Sacramento, Calif., courtroom in April. Randy Pench/Sacramento Bee/TNS via Getty Images hide caption
DNA isolated from a small sample of saliva or blood can yield information, fairly inexpensively, about a person's relative risk of developing dozens of diseases or medical conditions. GIPhotoStock/Cultura RF/Getty Images hide caption
As mother and daughter, Carmen and Gisele Grayson thought their DNA ancestry tests would be very similar. Boy were they surprised. Meredith Rizzo/NPR hide caption
