I'm tempted to say that homosexuality is innate. There was a segment on 60 Minutes once where there were a couple twins that were boys and one of them was all about the GI Joes and the other was into girly stuff and even wore nail polish. Both of them were raised by the parents the same way and they were still in elementary school, so it's not like their outside environment had that much an affect on their lives so far.

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