Science News reports that a large study has uncovered four genetic variants that may influence whether someone has had a same-sex sexual partner.
The Broad Institute's Andrea Ganna described at the recent American Society of Human Genetics meeting work done by him and his colleagues in which they performed a genome-wide association study of 490,000 individuals who were asked in a survey about their sexual partners. From this, they found two variants that appeared to influence sexual partner choice among men and two that influenced it among both men and women, Science News adds. According to Stat News, one of the variants is linked to an olfactory receptor — which has previously been linked to attraction — while another is linked to male-pattern baldness, indicating a possible hormonal influence.
"There is no gay gene," Ganna tells Science News, "but rather non-heterosexuality is influenced by many tiny-effect genetic factors."
Northwestern University's J. Michael Bailey tells Science News that this study is a step up over previous studies in the field due to its sheer size. At Stat News, however, the University of Padua's Andrea Camperio-Ciani criticizes the study as "a lot of useless curiosity," and is concerned that it could lead to discrimination or worse. Dean Hamer, though, disagreed. "I think it's much more important to know the scientific truth, than be in the dark. It's ignorance that's always hurt gay people," he tells Stat News.