Researchers who studied the genes and sexual preferences of roughly half-a-million people say that “a gay gene” that determines sexual orientation likely doesn’t exist.
The research team, composed of scientists from Denmark, Sweden, the U.K., and the U.S, published their findings Thursday in Science Magazine. The team studied the genes of more than 470,000 people using databases such as 23andMe and UK Biobank.
The study shows there is “an important role for the environment in shaping human sexual behavior and perhaps most importantly [that] there is no single gay gene but rather the contribution of many small genetic effects scattered across the genome,” said Ben Neale, the study’s author.
Neale is director of genetics in the Stanley Center for Psychiatric Research at the Broad Institute of MIT and Harvard University. Neale and his team consulted LGBT advocacy groups and science communications groups before publishing, seeking advice on how best to explain it to an unscientific audience.
Neale’s team identified five genetic markers that were “significantly” linked to sexuality. When all five markers were present, however, the individual had a less than 1% greater chance of same-sex attraction.
The groups that offered feedback on the study pointed out “caveats,” such as that the study did not account for if someone’s gender matches their sex. Because the study only identified people by if they had had sex with someone of the same gender, the groups said the study left out everyone that was gay but had not acted on their attractions.
