It was believed that homosexual contacts are largely explained genetically: according to some studies, sexual orientation is hereditarily explained by about 30-40 percent. However, this was not the case.
Scientists conducted a genome-wide analysis of associations involving almost 500 thousand people and identified five genetic loci that are associated with the likelihood of homosexual intercourse. The detected polymorphisms, however, explain such contacts by 8–25 percent, which does not allow us to consider orientation as the work of only one or several specific genes, scientists write in the journal Science.
For simplicity of analysis, the last variable was made binary: it is necessary to clarify that the authors did not focus on sexual orientation, but on whether each of the participants had had sexual contact with a person of his or her gender, the participants were divided into “heterosexual” by this attribute and non-heterosexual. The analysis was carried out using a genome-wide search for associations , which allows us to correlate single nucleotide polymorphisms (gene variations in one nucleotide) with certain traits.
Scientists also examined in detail the genetic correlation between homosexual sexual contact and other traits, as well as various diseases. So, sexual contact with a person of their gender was genetically correlated with the manifestation of risky behavior (it includes smoking, alcohol and marijuana consumption) in men and women, with the presence of depression in men and women, as well as the presence of anxiety in women. In addition, women showed a correlation with the number of sexual partners.
This study found it difficult to publish – on the one hand, it clearly shows that there is no such thing as a “gay gene.” But, on the other hand, politicians from different countries can refer to it when passing laws on gay propaganda, gay parades or on the prohibition of adoption of children by homosexual couples – since homosexuality is only a quarter due to genetic factors, the remaining three quarters are external factors – education and the environment.