By: Harini P
The idea of a “gay gene” contributing to the sexual orientation of a person was first conceptualised in the year 1993. Dean Hamer, an American geneticist from New Jersey, proposed that a correlation existed between the polymorphic marker xq28 and male homosexuality. His research group’s first paper, published in Science in 1993, reported that maternal, not paternal male relatives of gay men had increased rates of same-sex orientation, suggesting the possibility of sex-linked transmission in a portion of the population. However, this claim was attested by many, including a study conducted on 52 gay male sibling pairs from Canadian families by Rice et al. The study directly contradicted Hamer’s work, claiming no such correlation exists; therefore, no X-linked gene was the underlying cause of male homosexuality. In 1993, Risch et al. suggested in a letter that a “major gene linked to homosexuality is unlikely due to selection pressures against survival”.
A similar claim to that in Risch’s letter was made again by Sam Jones, a Madrid Correspondent for the Guardian, in 2004. He stated in his article “Genes for gay men make woman fertile”- a mockery of what he attempted to contradict that- “If male homosexuality is genetic, and homosexuals reproduce less than heterosexuals, the trait should eventually disappear.” In this case, he referred to the “Darwinian paradox of Gayness”. Similar to Risch, Jones was also directly contradicting the study conducted by Camperio-Ciavi, where they reported that homosexuals, in particular, have more maternal than paternal male homosexual relatives, that homosexual males are more often later-born than first-born, and that they have more older brothers than older sisters.
Not limiting itself to genetics, in 1991, Simon Levay, perhaps the precursor to all of this, released a study concluding that a part of the brain was linked to sexuality. He suggested that the small differences in the size of certain cells in the brain could influence sexual orientation in men. To top it off, he claimed that ‘homosexuality’ had a ‘biological substrate’. Anne Fausto-Sterling, an American Sexologist, pulled apart his claims in her book “Sexing the Body”, in the year 2000.
In the 90s to early 2000s, any possible ‘scientific findings’ regarding the existence of a gay gene as a genetic or biological factor linked to homosexuality were blown out of proportion, milked for all their worth, regardless of the weight or substantial evidence supporting their claims. The need for a scientific purpose to explain the concept of homosexuality was taken advantage of by media outlets who heard the word ‘homosexuality’ in a scientific paper and headlined it with ‘discoveries towards gay gene’, even if the paper contradicted the existence of such a gene or was not even a genetic study. It was not something that went unnoticed by scientists in the field, who, on their own, revelled in the attention received, conducting sociological studies with biased population groups to make unsupported claims regarding the genetics of sexual orientation.
In 2019, the most extensive genetic study to analyse same-sex behaviour was conducted, revealing insights into the genetic architecture of homosexuality. The study was conducted on 493,001 participants from the United Stands, United Kingdom, and Sweden to study genes associated with sexual behaviour. They found not one “gay gene”, and multiple genetic factors that could be attributed to non-heterosexual behaviour. The study shows that genes play a small and limited role in determining sexuality. Genetic heritability — all of the information stored in our genes and passed between generations — can only explain 8 to 25 per cent of why people have same-sex relations, based on the study’s results.
Moreover, the researchers found that sexuality is polygenic — meaning hundreds or even thousands of genes make tiny contributions to the trait. That pattern resembles other heritable (but complex) characteristics like height or a proclivity toward trying new things. (Things like red/green colour-blindness, freckles and dimples can be traced back to single genes). But polygenic traits can be strongly influenced by the environment, meaning there’s no clear winner in this “nature versus nurture” debate.
The news that the most extensive study of its kind failed to confirm the existence of a ‘gay gene’ is not so much a disappointment for those looking to understand the LGBTQ community as it is an acknowledgement that science does not need to tell us what should be obvious: gays, lesbians, bisexuals and pansexuals are who they are. “This new research provides even more evidence that being gay or lesbian is a natural part of human life, a conclusion that has been drawn by researchers and scientists time and again. The identities of LGBTQ people are not up for debate. This new research also reconfirms the long-established understanding that there is no conclusive degree to which nature or nurture influences how a gay or lesbian person behaves,” says GLAAD’s Zeke Stokes, once again reiterating that genetics does not tell the whole story.
