I tend to believe most,if not all, of that.
However, I have never known anyone that chooses to be persecuted and treated as a second class citizen as homosexuals were for centuries.
Accordingly, it may not be genetic but it is definitely not by choice. If it ain't genetic then what else is it when you are born that way?
Did you choose your sexual orientatation? No offense but I never did. I was born with mine.
That is how it works with sexual orientation. I know no one that chose so so how could it be choice?
See, I never said it was a choice, although I believe that choice is part of it. Science is pretty split on the issue of free will, and I am now considering coming down somewhere in the middle, some people have free will, and some don't.
I know one homosexual who insist that he made the choice, despite the possibility of persecution, I also know more who insist that they did not have a choice. Thinking back myself I always liked what I like sexually, but I also believe I choose what I actually do. The debate about free will is one that is not going to be solved anytime soon.
Let us assume that sexuality is not a choice, and that it is not genetic. It could be a result of chemical reactions in the womb from the mothers diet, or something that happens after the child is born. It could be environmental and still not be choice, or it could simply be a random fact in child development and independent of environment or genetics. The latter seems unlikely though.