Born that way?.

Is there a genetic explanation for homosexuality? Simon LeVay, neuroscientist at the Salk Institute, San Diego, California, investigates and considers the social and ethical implications of such an explanation. He retraces his own experiences as the gay son of a puzzled but resigned father, and in recounting the history of attitudes to homosexuals he shows some extraordinary German archive film of sexual-re-orienting experiments on rats and of brain surgery on male patients aimed at "correcting" their homosexuality.