Scientists may have put the “born this way” question to bed, having discovered what they say is an epigenetic rather than genetic link that connects mothers with gay sons and fathers with lesbian daughters:
The hereditary link of homosexuality has long been established, but scientists knew it was not a strictly genetic link, because there are many pairs of identical twins who have differing sexualities. Scientists from the National Institute for Mathematical and Biological Synthesis say homosexuality seems to have an epigenetic, not a genetic link.
Long thought to have some sort of hereditary link, a group of scientists suggested Tuesday that homosexuality is linked to epi-marks — extra layers of information that control how certain genes are expressed. These epi-marks are usually, but not always, “erased” between generations. In homosexuals, these epi-marks aren’t erased — they’re passed from father-to-daughter or mother-to-son
William Rice, an evolutionary biologist at the University of California Santa Barbara and lead author of the study explains: “These epi-marks protect fathers and mothers from excess or underexposure to testosterone—when they carry over to opposite-sex offspring, it can cause the masculinization of females or the feminization of males.”
And that’s where gay babies come from.
Rice’s model still needs to be tested on real-life parent-offspring pairs, but he says that’s the easy part and will be able to determine if his theory is correct within a matter of months.
There you have it. Science.