Summary

In this chapter, Mukherjee discusses the connection between genes and sexual identity. He writes about the work of Dean Hamer, and his "search for the gay gene" (371). Mukherjee also writes about the work of J. Michael Bailey in the 1980s which found that genes influenced homosexuality "almost as strongly as genes influence height" (374). In 1993, Hamer eventually concluded that the gay gene had to be carried on the X chromosome and was able to identify the small stretch of the chromosome where the gene is located. Since then, other studies have both confirmed and contradicted Hamer's findings but "thus far, no one has isolated an actual gene that influences sexual identity" (378). Mukherjee writes that sexual identity is likely to be governed by "multiple genes with small effects—in particular, genes that modulate and integrate inputs from the environment" (378).

In the next...