jewishfeminist,
As I noted above, there are studies on both sides of the issue. The twin studies indicate that there are both genetic and environtmental factors. Even LeVay and Hamer don’t claim that it is all biological.
The LeVay and Hamer piece doesn’t really speak that much to the causes of homosexuality. Rather it speaks to practicing homosexuals having differences in their brains than heterosexuals. There is no indication of cause and effect, and LeVay and Hamer don’t claim that their findings showed a genetic cause, or that homosexuals are “born that way.”
Furthermore, other researchers (William Byne’s team) have not found statistically significant differences in the INAH3. LeVay and Hamer’s study itself involved quite a small sample size.
Finally, if you are going to call bias, it is only fair that you mention that both LeVay and Hamer are themselves gay men.