Millions of people have handed their DNA over to genetic testing companies like Ancestry or 23andMe to learn more about their family trees. But when you ship off your saliva, law enforcement could have access to your DNA. Police could use genetic information it gets from those companies to identify you in a criminal investigation, even if you’ve never used one of those services. Jacksonville resident Eric Yarham wanted to learn more about his family tree, so he mailed off his saliva to 23andMe. “Just trying to unravel the mystery that is your genetics,” said Yarham, who lives in the...