Molecular biologist Kaye Lang's theory--that ancient diseases encoded in the DNA of humans can return to life--has become a chilling reality. The shocking evidence: a "Virus-hunter" Has tracked down a flu-like disease th...Molecular biologist Kaye Lang's theory--that ancient diseases encoded in the DNA of humans can return to life--has become a chilling reality. The shocking evidence: a "Virus-hunter" Has tracked down a flu-like disease that kills expectant mothers and their offspring.