The relevant fact to the point I made remains: the OP corroborates that there is no known genetic cause of homosexuality -- there's now not even a genetic cause suspected.
That corroborates the recent scientific presentation that homosexuality's etiology is indeed not genetic at all but is epigenetic, a gestational epigenetic abnormality, a birth defect.
Ideologues would do well to stop embarrassing themselves on the matter and instead pause for a moment to reflect what the birth defect reality of homosexuality means.
It means that bullying will be greatly reduced as a result, it means that religious fundamentalists will stop trying to "convert" homosexuals to homosexuality (a painful process for the homosexual), it means that scientific research to find a prevention for the birth defect of homosexuality could be months away from providing a simple vitamin supplement to the pregnant woman (like was done to greatly reduce the incidence of other gestational epigenetic birth defects like spina bifida) to prevent their offspring from having the intrinsic misery-creating birth defect of homosexuality, and in no way should all of this compromise the equal-rights or political position of those supporting equal rights for those suffering from homosexuality, indeed, discrimination should reduce as a result of accepting the epigenetic birth defect reality of homosexuality.
Though I can understand the existence of the irrational fear of ideologues and activists, it's simply that: irrational .. and, when the matter is considered rationally, there's really no reason not to simply accept the benefits that come with accepting the scientific truth of the matter as I've presented it.