New Sexual Orientation Study Suggests

Researchers Dr. Andrea Burri and Dr. Qazi Rahman based their study on the idea that there are consistent differences in the psychological characteristics of female children and male children, and on prior research that suggests those who become gay as adults have different characteristics from those who don’t (previous research suggests about a third of gender non-conforming girls and 50-80 per cent of gender non-conforming boys turn out to be gay later in life).

In the study published this week in PLoS One, a peer-reviewed science journal, Burri and Rahman looked at sexual attraction, childhood gender typicality, and adult gender identity in 4,425 female twins and found that both a shared set of genes and a shared set of environmental factors are partially responsible for gender non-conformity and female sexual orientation.

“We found that there is a connection between these mental traits and how sexual orientation develops. One idea is that there is an association between these psychological traits and sexual orientation because they all develop under common biological drivers; like the development of brain regions under the influence of genes and sex hormones. We think environmental factors and genetics drive other mechanisms, like exposure to sex hormones in the womb, to shape differences in gender nonconformity and sexuality simultaneously.”

This is a good thing because it supports the idea of genetics playing a strong part in sexual orientation, which is a key argument in countering the idea, frequently supported by the anti-gay crowd, that being gay is always a choice. But it’s less good because of “substantial measurement error.” In the discussion of the study, the authors note that, despite the large sample size, there weren’t enough non-heterosexual participants; that results related to sexual orientation are “notoriously skewed”; and that some of their parameter estimates, especially for adult gender identity, were imprecise.

Nevertheless, this study is a strong piece of evidence in counteracting what is one of the most harmful myths about being gay — the idea that it’s always a choice, or a learned behaviour that can be un-learned.