An ancestry database holds the key to catching a killer in this explosive medical thriller from New York Times-bestselling author Robin Cook.When the body of social worker Kera Jacobsen shows up on Chief New York City Medical Examiner Laurie Montgomery's autopsy table, it appears she was the victim of a drug overdose. But for Laurie and her new pathology resident, the brilliant Dr. Aria Nichols, little things aren't adding up. Kera's family and friends swear she never touched