"I see sexuality in the same way that I see skin colour and can only hope that the Church will eventually accept what the scientists are saying."
When a friend said that to me a while back it made me want to find out more about what the scientists really were saying. Here is a link to an article which, as far as I can tell, summarises the latest research. I think it will help us when we talk to friends who assume that sexuality is simply a matter of genetics.