The Science of Desire: The Search for the Gay Gene and the Biology of Behavior

In this admirably lucid and surprisingly lively book, Hamer, chief of genetic research at the National Cancer Institute, assisted by Copeland, a correspondent for the Scripps-Howard newspaper chain, recounts his discovery of a pattern on the X chromosome that, in families with two gay brothers, 33 out of 40 such pairs share. He was thus able to link sexual orientation with genetic makeup. This discovery is all the more noteworthy when we consider, as Hamer points out, ``the scientific literature contains more articles on the genetics of eye color in fruit flies than on the biology of human sexuality.'' He is careful to explain that genetic predisposition alone does not ``cause'' homosexuality; environmental factors must also be taken into account, and a complete picture of the genesis of homosexuality is still far in the future. Hamer simplifies complex ideas for general readers (the structure of interlocking strands of DNA is described as ``chemical Velcro'') and explores the ethical implications of a ``gay gene'' with laudable compassion and common sense. (Oct.)