Homosexuality not genetically determined, says study

A new study has shown that there is no such thing as a “gay gene” — but there is a mix of genetic and environmental factors which influence sexual behavior.

The research comes on the back of calls by the LGBT groups and human rights against social discrimination on account of people’s sexual orientation.

Coupled with cases of sexual disorientation and eventual self-acceptance, the longstanding but unanswered question of whether or not the choice of being a homosexual or heterosexual is determined by genetic factors has always been in the fore.

However, a recent study conducted by MIT/Havard researchers and published in the journal ScienceMag has concluded that there are no genes in humans responsible for making a person gay or determining people’s sexual behaviour or orientation.

The researchers proceeded by scanning the genomes (entire genetic make-up) of a total of 409,000 participants who signed up to the UK Biobank project, and 68,500 others that registered with 23andMe, a genetics company.

After the participants were drilled to find out their sexual behaviours as to whether they had same-sex partners exclusively or as well as opposite-sex partners, the researchers found that genetics could only account for between 8 to 25 percent of same-sex behaviour across the population.

While only five genetic variants were linked to same-sex behaviour (including that for the biological pathway for smell and those for sex hormones), they all-together accounted for less than one percent of same-sex behaviour.

Ben Neale, researcher and associate in the analytic and translational genetics unit at Massachusetts General Hospital, said that, although genetics proved to be an important “contributing factor” in determining “sexual behaviour”, there are no single gay genes.

“Genetics is less than half of this story for sexual behaviour. There is no single gay gene, and a genetic test for if you’re going to have a same-sex relationship is not going to work. It’s effectively impossible to predict an individual’s sexual behaviour from their genome,” he said.

David Curtis, professor at UCL Genetics Institute, said that, although the study “clearly shows that there is no such thing as gay gene”, this doesn’t mean homosexuality is not in some way an innate and indispensable part of an individual’s personality

“There is no genetic variant in the population that has any substantial effect on sexual orientation. Rather, what we see is that there are very large numbers of variants which have extremely modest associations,” he said.

“Even if homosexuality is not genetically determined, as this study shows, that does not mean that it is not in some way an innate and indispensable part of an individual’s personality.”

Ecuador highest court had recently approved same-sex marriage in a new landmark ruling while Botswana decriminalised homosexuality in a similar case that ended in favour of gay rights campaigners.