Sierra Bouzigard was 19 years old when she was murdered and left beaten beyond recognition by the side of a road in Lake Charles, Louisiana. Before she died, she fought back, scratching her attacker and leaving bits of skin containing her killer’s DNA underneath her fingernails.
Police are looking for the killer using that scrap of genetic material—but not the way you might think. In this case, the killer’s DNA didn’t match any suspects or criminal database, so scientists are using the DNA to assemble a high-tech version of a tried-and-true investigative tool: a sketch of the killer’s face.
(Read more in “How Science Is Putting a New Face on Crime Solving” in the July issue of National Geographic.)