Talk of a "gay gene" makes no sense, unless you know how the biological process works.
In mammals, sex is determined genetically, but not "gender association". That is, in the early part of the life of a fetus, its sex is determined to either be male or female.
But only much later, during the gestation period, does a release or the lack of a release of the hormone testosterone tell the brain of the fetus that it is male or female.
Scientists have known this for almost 50 years now. In animals, they have both given female fetuses that little "squirt" of testosterone to the brain, so they developed with "male" brains though they had female genitalia; and they blocked that "squirt" of testosterone in male fetuses, so they grew up with "female" brains, though they had male genitalia.
In either case, these "interfered with" animals exhibited homosexual behavior. Importantly, when only *half* of their brain received testosterone, they became bisexual, and exhibited both male and female mating behaviors.
So any suggestion of a gay gene would have to be focused on the mechanism that *coordinates* either that "squirt" of testosterone, or the lack of it, with the appropriate gender, or interferes with that coordination.
Importantly, for almost as long, they have known that plant estrogens can interfere with this process. That is, female plant hormones are close enough to mammalian female hormones as to cause problems. (The two foods that contain the most natural female plant hormones are yams and tofu.)
However, for many years, farmers have been spraying crops with female plant hormones to stimulate growth, significantly increasing the publics ingestion of these hormones. But though there has been much research about this, few scientific conclusions can be drawn as to its long term effects.
So this means that homosexuality may be caused by a gene, or by some interference during gestation, and most likely can be further developed or inhibited by environment.
So this means that homosexuality may be caused by a gene, or by some interference during gestation, and most likely can be further developed or inhibited by environment.
I disagree. Furthermore I don't think same-sex attraction can be caused by any one gene. What the experts say is some children exhibit gifts that some incorrectly interpret to imply the child is homosexual. Checkout: How Might Homosexuality Develop? Putting the Pieces Together