To what extent do genes determine human behavior? Human destiny? With vivid imagery and fascinating examples, this program looks at how genetic screening yields answers to riddles past and future. A woman discovers that a single letter change in the genome has been responsible for her family’s generations-old "curse" of deformed hands. Dr. Hugh Montgomery of University College Hospital, London, screens the DNA of army recruits for the ACE or endurance gene which may affect their longevity as well as their basic training. Dr. Dean Hammer of the National Institutes of Health explains his search for a thrill-seeker gene, D4DR. And attorney Daniel Summer argues for leniency for his death-row client because his DNA predisposed him to a life of crime. Professor Lee Silver of Princeton University and Nobel Laureate Sir Paul Nurse also provide commentary. A BBC Production. (50 minutes)