Discovery of 'Gay Gene' Questioned

Six years ago, molecular geneticist Dean Hamer and his colleagues at the National Cancer Institute (NCI) announced to great fanfare that they had found a genetic link to male homosexuality. Their work indicated, they said, that an as yet unidentified gene on the X chromosome influences who develops the trait (Science, 16 July 1993, p. 321). Researchers were excited by the possibility of one day learning the biological basis for sexual orientation but also wary, given that initial reports of genetic linkages for other complex traits, such as manic depression and schizophrenia, had fallen apart under further scrutiny. Now the “gay gene” linkage may be suffering a similar fate.