Why is something that obviously should well be evolutionarily wiped out (if it is indeed due to genes/people can't help it) not, by now?
(Corollary question if you say "there is no evolution, it's intelligent design" - ok then what the heck purpose would homosexuality serve in this design? Honest question, I'm not being a smartass.)
Edit - PS you know you're over some kind of target if an OP gets downpoots.
FDA approved the endocrine disrupting chemical diethylstilbestrol (DES) for 50+ years for expecting mothers. It was used A LOT. It was unapproved by FDA in the 70s and phased out over time. It causes a high level of mix-matched hormonal / brain / genitalia issues in the offspring, as well as in the descendants of those offspring. Also caused other behavioral issues in the children and grand children of the mothers who were given it.