The FBI has struck up a partnership with one of the largest at-home DNA testing services, according to BuzzFeed News. Apparently, Family Tree DNA has allowed the agency to access its genealogy database containing the DNA profiles of over a million users. Law enforcement has been using the public's increasing fascination with DNA testing as a tool to crack cases for quite a while now. But this is reportedly the first time a private firm has willingly given authorities access to its repository.