I used to agree... but i now doubt that our mind is purely physical.. No one can explain how we are concsious.. or where in the brain our actual thoughts are taking place... there must be an un-explained part of our thinking.
That is true, no one knows yet. The brain is a very complex and mysterious organ.. But it is there in the brain somewhere.
People don't want to admit that some are born gay, because that would disallow discrimination against them. But I am 100% certain that you can born gay