In what could be a big blow against those who argue that LGBT is a “lifestyle choice,” scientists may have found what could be the LGBT genetic link to sexual orientation.
Researchers at the North Shore University in Illinois have discovered two gene variants that can be found in gay men, which could mean that sexual orientation is partly determined by genetics.
Looking for the LGBT genetic link
The genome-wide association study, which was published in Scientific Reports and looks into how DNA is linked to a particular trait, had the purpose of determining how sexual orientation develops from the womb.
However, it should be noted that the study doesn’t address homosexuality in women as the scientists looked into DNA sequences from 1,077 gay men and compared them to 1,231 heterosexual men.
Determining the single-letter differences in their genomes, they saw that onene gene was found in chromosome 14 that’s mainly active in producing/ maintaining thyroid.
Meanwhile, the other was located in chromosome 13, which is active in one section of the brain called the diencephalon.
The latter also contains the hypothalamus, which had been identified in 1991 as different in size between gay and straight men.
The LGBT genetic link to the biological
Prior research work had discovered that the said gene, called SLITRK6, is active in the hypothalamus of male mice fetuses before they’re born.
“This is thought to be a crucial time for sexual differentiation in this part of the brain,” said neuroscientist Simon LeVay, who made the hypothalamus discovery in 1991.
“So this particular finding is a potential link between the neuroanatomy and molecular genetics of sexual orientation,” said LeVay of the recent genetic discovery.
“It adds yet more evidence that sexual orientation is not a ‘lifestyle choice’,” said geneticist Dean Hamer of the National Institute of Health, who first suggested the idea of a ‘gay gene’ in 1993.
However, with this discovery, scientists want to avoid having homophobes labeling being gay as a “disability” or parents aborting gay babies, and that being gay isn’t something that can be switched off or on.
“There are probably multiple genes involved, each with a fairly low effect,” said North Shore University’s Alan Sanders, who was the lead of the recent study.
“There will be men who have the form of gene that increases the chance of being gay, but they won’t be gay,” Sanders said.
LGBT genetic link still ‘speculative’
Moreover, some researchers have said the results may be “best described as speculative.”
Dr. Nina McCarthy of the University of Western Australia said: “As this study was carried out in European men, we do not know whether the findings will apply to homosexuality in women, or even to homosexuality in non-European men.”
McCarthy said that taking into consideration any genome-wide association study, “it’s really important to appreciate that association does not imply causation.”