[freespirited]

Congenital adrenal hyperplasia causes girls to be exposed to excessive levels of testosterone in utero. Even though the condition is typically corrected at birth, when diagnosis is made, these females are much more likely to have male interests and behaviors (eg more interested in sports than average girl) and be lesbians once old enough to have a sexual preference.

For males, however, I think any biological basis is probably something other than sex hormones.

[StolarStorm]

There have to be some gay freepers around. Yes, there are plenty of gay conservatives. Maybe they could shed light on this topic (everyone... be nice).

If they never remember a time when they were attracted to women, and never had an event or person that influenced them to be gay, that would sure seem like a bit of anecdotal evidence that biology plays a part.