This will be a debate until the end of time, and is actually pointless as it only raises other issues that cause arguments. As a gay female, I can't tell you that I was born gay, but I also can't tell you that I wasn't. Do you remember liking boys when you were an infant? As for me, I had my first crush in the third grade, and it just so happened to be a girl.
So, I don't think there will be an answer to this question for a very long time.