Science has yet to definitively declare a “gay gene” — probably because all those evil-gelicals would abort their gaybies left and right
If they find the "gay gene" it won't be the evangelicals -- in fact the ONLY gay babies will probably be evangelicals who won't kill and will try to use other means to "convert" the baby as it grows.
No, deep in their heart even liberals tolerate homosexuals because they HAVE to and to do so gives them a sense of superiority and the ability to virtue signal. Just as the voting booth is private people who said they would not vote for Trump did so, so will 99% of people end the gestation process for known gay embryos.
There is a biological REASON the initial, visceral reaction to same-sex kissing is revolt and disgust: it is b/c it is unnatural and just wrong, like pedophilia and eating feces. You can't nag or legislate that reaction since it is instinctive.
We are seeing that already with Downs' Syndrome -- very few except the very religious are choosing to keep babies with it.
And that my friends is a complete fact. If they discover a "gay gene," gays will disappear inside of 2 generations.