Sexual orientation refers to the sexual attraction of men, women, or both sexes. Those who accept homosexuality see it as a genetic cause, as opposed to those who believe it is a socially induced choice. According to a 2016 literature review, there would be considerably more robust cross-cultural evidence supporting genetic rather than social causes: non-compliance with biological sex during childhood would be strongly associated with homosexuality at home. adulthood; sexual orientation would not change despite social or surgical sexual transition; studies demonstrate genetic influences in twins; the birth order of boys in a family would be a significant factor. On the contrary, evidence of the social causes of homosexuality, ie recruitment, sexual abuse, negligent or homosexual parents, or a greater or lesser social tolerance, remain weak and distorted by several factors. confounding.
A large international study (nearly 500,000 people), recently published, has attempted to find the genes associated with ‘non-heterosexual’ activity and orientation. The participants’ genetic and personal information (questionnaires) from UK Biobank, a database of 500,000 people from the United Kingdom, as well as data from 70,000 people from the US 23andMe genetic identification service, reportedly was analyzed by focusing on a few issues such as sexual fantasies, the degree to which they identified as being gay or heterosexual, and whether they had ever had, at least once, a sexual relationship with a person of the same sex . Of the millions of genetic variants analyzed, only five variants could be identified specifically for who answered ‘yes’ to the last question. These variants would appear in less than 1% of subjects, too few to predict sexual orientation. Using a different analytical technique, the authors claim that genes could influence 8% to 25% of this behavior. In short, they found virtually nothing in common in subjects who had at least one non-heterosexual experience in their lifetime. These results, they say, suggest that other genetic markers would be discovered with much larger cohorts. They assume that it would be impossible to predict sexual orientation, because too many genetic variants, perhaps thousands, would be involved, and environmental factors or during pregnancy could explain what they do. could identify. Several groups and LGBT activists saw in these findings the claim that sexual identity and orientation are diverse, malleable, and complicated, but deplore the fact that gender identity, as opposed to biological sex, and all the variety of sexual interests, have not been taken into consideration. Some gay academics lobbied to ban the publication of this study, citing discrimination and LGBT security, as it seemed to be leaning heavily toward social causes. Some wonder, given the insignificant results, why this study was published. Others criticize researchers for carrying out their analyzes of sexual behavior instead of inherent sexual attraction. Dean Hamer, a geneticist who had discovered a ‘gay embarrassment’ in 1993, exclusively analyzing homosexual individuals, said the study was not about sexual orientation, but rather about what motivates an individual to have a sexual orientation. , or several non-heterosexual experiences. By the way, his gay embarrassment has not been found!