||12-03-2012 09:52 PM
there's been research done that proves and disproves the existence of altered X chromosomes for homosexuals, suggesting that genetic alteration may or may not occur.
obviously, this does not help determining one way or the other.
I wouldn't compare it so much as genetics vs. choice, but more as a preference? if you've never had a taste for spicy foods, the odds that you will one day wake up and decide to only eat curry for the rest of your life is unlikely. similarly, if you have always preferred, as a female, female anatomy, the odds are that you will wake up and decide to jump on some guy are unlikely.
sexuality in general tends to be a more fluid trait as opposed to something like hair color...for example, I identify as a straight female, and find most women physically attractive but not sexually attractive. In my experiences [anecdotal evidence], a lot people experience this to some degree. appreciating the physique of the same sex while not finding it sexually attractive...so I believe it would be just as likely for someone to experience the reverse [i.e., appreciating the physique of the opposite sex while not finding it sexually attractive].