The New York Times reports:
How do genes influence our sexuality? The question has long been fraught with controversy. An ambitious new study — the largest ever to analyze the genetics of same-sex sexual behavior — found that genetics does play a role, responsible for perhaps a third of the influence on whether someone has same-sex sex. The influence comes not from one gene but many, each with a tiny effect — and the rest of the explanation includes social or environmental factors — making it impossible to use genes to predict someone’s sexuality.
“I hope that the science can be used to educate people a little bit more about how natural and normal same-sex behavior is,” said Benjamin Neale, a geneticist at the Broad Institute of M.I.T. and Harvard and one of the lead researchers on the international team. “It’s written into our genes and it’s part of our environment. This is part of our species and it’s part of who we are.”
Science News reports:
First reported at a genetics conference in 2018, the study found five genetic variants associated with having a same-sex sexual partner (SN: 10/20/18). But those variants, called SNPs, don’t predict people’s sexual behavior, researchers report in the Aug. 30 Science.
“There is no ‘gay gene’ that determines whether someone has same-sex partners,” says Andrea Ganna, a geneticist at the Broad Institute of MIT and Harvard and the University of Helsinki.
Family studies have suggested that genetics account for about 32 percent of heritability of homosexual behavior. But each SNP, or single nucleotide polymorphism, has a very small effect on whether someone has ever had a same-sex sexual partner, the new research found.
The Washington Post reports:
Andrea Ganna, lead author and European Molecular Biology Laboratory group leader at the Institute of Molecular Medicine in Finland, said the research reinforces the understanding that same-sex sexual behavior is simply “a natural part of our diversity as a species.” The new study, published Thursday in the journal Science, is not the first to explore the link between genetics and same-sex behavior, but it is the largest of its kind, and experts say it provides one of the clearest pictures of genes and sexuality.
The researchers were able to find five genetic variants that were statistically associated with same-sex sexual behaviors, but none had a large effect and none could itself predict same-sex behaviors. One of the variants was found in a stretch of DNA that includes several genes related to the sense of smell. And another one of the genes is related to male pattern baldness, which the authors said could suggest that sex hormone regulation may somehow be involved.
The haters will, of course, seize of “no gay gene” headlines and ignore the complexities of the actual research, which is hardly touched upon by news snippets like those above. And it’s worth noting that the study already has pro-LGBT critics, for reasons both scientific and cultural.