The largest study of its kind ever conducted has debunked the idea that a single so-called “gay gene” exists, instead suggesting our sexual preferences are influenced by a complex mix of our genes, environment, and life experiences.
Looking at the genes of nearly half a million people drawn from existing UK genetic databases, an international team of researchers identified five spots on the human genome that are linked to same-sex sexual behaviour – but none which are reliable enough to predict someone’s sexuality.
The controversial idea of a single “gay gene” dates back to 1993, when a region of the human genome called xq28 was linked to male homosexuality.
“Those research findings have not been replicated,” says The Economist, “But it was never going to be that simple: decades of genetic research have shown that almost every human characteristic is a complex interplay of genes and environmental factors” and the latest study “confirms that this is the case for human sexuality, too”.
The study estimated that about a third of the variation in same-sex behaviour is explained by genetics, which, authors say chimes with previous studies that put the figure at about 30% to 50%, with the rest influenced by environmental and cultural factors.
“The research is the latest effort in a decades-long quest to understand the inherited component of sexuality,” says NPR and “broadly reinforces the observation that both biology and a person’s environment influence sexuality, but the results reveal very little about that biology”.
To ensure that their results were not misinterpreted, researchers worked with LGBTQ advocacy groups and science-communication specialists on the best way to convey their findings to the public. “Their efforts included the design of a website that lays out the results — and their limitations — to the public, using sensitive, jargon-free language”, says Nature.
“It found that the sex of your sexual partners is, in fact, influenced by your genes”, writes Dr Steven Phelps and Dr Robbe Wedow in the New York Times. “But it also found that it was not possible to predict your sexual behaviour from your DNA alone. The study suggested, in other words, that while biology shapes our most intimate selves, it does so in tandem with our personal histories — with the idiosyncratic selves that unfold in a larger cultural and social context”.
While researchers agree the findings just scratch the surface, “the most important takeaway from the study is that it should further dispel the harmful narrative of same-sex behaviour being an aberration to be identified and presumably cured — one that’s been fueled by flawed or cherrypicked genetic research,” says Gizmodo.
“Like so many things about people, the authors noted, our sexuality is nuanced and influenced by everything that surrounds us,” says the website.