We May Have Just Identified Genetic Evidence of Male Sexual Orientation

Scientists are reporting what could amount to be the firmest evidence yet of genetic links to male sexual orientation, in the first published genome-wide association study (GWAS) examining the trait.

Researchers recruited more than 2,000 men of both homosexual and heterosexual orientation and analysed their DNA, identifying two genetic regions that appear to be linked to whether individuals are gay or straight.

"Because sexuality is an essential part of human life – for individuals and society – it is important to understand the development and expression of human sexual orientation," says psychiatrist Alan Sanders from NorthShore University HealthSystem in Evanston, Illinois.

"The goal of this study was to search for genetic underpinnings of male sexual orientation, and thus ultimately increase our knowledge of biological mechanisms underlying sexual orientation."

To do so, Sanders' team studied 1,077 homosexual men and 1,231 heterosexual men of primarily European ancestry, who were respectively recruited from community festivals and a nationwide survey.

For the purposes of the study, the men's sexual orientation was based on their self-reported sexual identity and sexual feelings. Each individual taking part provided a sample of their DNA in the form of blood or saliva samples, which were genotyped and analysed.

When the researchers sifted through the data, they isolated several genetic regions where variations called single nucleotide polymorphisms (SNP) signalled single-letter changes in the DNA, with two of the most prominent congregations located near chromosomes 13 and 14.

https://www.sciencealert.com/we-just-identified-genetic-evidence-male-sexual-orientation-gay-gene