Two gene variants have been found to be more mon gay men. New Scientist looks at what this tells about the way blogy shap our sexualy
Contents:
- THERE IS NO ‘GAY GENE.’ THERE IS NO ‘STRAIGHT GENE.’ SEXUALY IS JT PLEX, STUDY NFIRMS
- WHAT DO THE NEW ‘GAY GEN’ TELL ABOUT SEXUAL ORIENTATN?
- THERE’S NO ONE ‘GAY GENE,’ BUT GEICS ARE LKED TO SAME-SEX BEHAVR, NEW STUDY SAYS
- 'GAY GEN': SCIENCE IS ON THE RIGHT TRACK, WE'RE BORN THIS WAY. LET’S AL WH .
- IS THERE A "GAY GENE"? MAJOR NEW STUDY SAYS NO
- IS THERE A “GAY GENE"?
- HOW OUR GEN ULD MAKE GAY OR STRAIGHT
THERE IS NO ‘GAY GENE.’ THERE IS NO ‘STRAIGHT GENE.’ SEXUALY IS JT PLEX, STUDY NFIRMS
* gene that makes you gay *
Dpe the numbers, many people still nsir homosexual behavr to be an anomalo choice. However, blogists have documented homosexual behavr more than 450 speci, argug that same-sex behavr is not an unnatural choice, and may fact play a val role wh populatns. The 2019 study is the latt a hunt for “gay gen” that began 1993, when Dean Hamer lked male homosexualy to a sectn of the X chromosome.
As the ease and affordabily of genome sequencg creased, addnal gene ndidat have emerged wh potential lks to homosexual behavr. So-lled genome-wi associatn studi intified a gene lled SLITRK6, which is active a bra regn lled the diencephalon that differs size between people who are homosexual or heterosexual. Wh multiple gene ndidat beg lked to homosexualy, seemed highly unlikely that a sgle “gay” gene exists.
In rats, manipulatn of hormon durg pregnancy produc offsprg that exhib homosexual behavr. Several hypoth have been advanced to expla how homosexualy n be beneficial perpetuatg faial gen. Gay uncl and nts, for example, are “helpers the nt” that help raise other fay members’ children to nurture the fay tree.
WHAT DO THE NEW ‘GAY GEN’ TELL ABOUT SEXUAL ORIENTATN?
” For example, certa gen women help crease their fertily, but if the gen are exprsed a male, they predispose him toward homosexualy.
While there is no sgle “gay gene, ” there is overwhelmg evince of a blogil basis for sexual orientatn that is programmed to the bra before birth based on a mix of geics and prenatal ndns, none of which the fet choos. The study of nearly a half ln people clos the door on the bate around the existence of a so-lled “gay gene. In s stead, the report fds that human DNA nnot predict who is gay or heterosexual.
It is worth keepg md that this study only vers some typ of sexualy — gay, lbian and cis-straight — but don’t offer many sights to genr inty. Humans have tried to unrstand human sexualy for centuri — and geics rearchers joed the ay the early 1990s after a seri of studi on tws suggted homosexualy ran fai. “As a teenager tryg to unrstand myself and unrstand my sexualy, I looked at the ter for “the gay gene” and obvly me across Xq28, ” said Fah Sathirapongsasuti, a study -thor and senr scientist at 23andMe, which he joked once led him to believe he hered his gayns om his mother.
THERE’S NO ONE ‘GAY GENE,’ BUT GEICS ARE LKED TO SAME-SEX BEHAVR, NEW STUDY SAYS
“We worried a lot about volunteer bias, ” said Bailey, whose rearch clus a wily publicized study on Xq28 and gay brothers om 2018. Sanrs llaborated wh Bailey on those earlier studi and said their work had always admted that there was no sgle “gay gene. The rearchers had members of the same-sex muny review the study’s sign and language, and they adm that their termology and fns for gay, lbian and heterosexual do not reflect the full nature of the sexualy ntuum.
In other words, tri to judge if a person leans gay, straight or bisexual.
“[Our study] unrsr an important role for the environment shapg human sexual behavr and perhaps most importantly there is no sgle gay gene but rather the ntributn of many small geic effects sttered across the genome, ” Neale said. We have known for s that sexual orientatn is partly herable men, thanks to studi of fai which some people are straight and some people are gay. In 1993, geic variatns a regn on the X chromosome men were lked to whether they were heterosexual or homosexual, and 1995, a regn on chromosome 8 was intified.
'GAY GEN': SCIENCE IS ON THE RIGHT TRACK, WE'RE BORN THIS WAY. LET’S AL WH .
Both fdgs were nfirmed a study of gay and straight brothers 2014.
Alan Sanrs at North Shore Universy, Illois, and his team ppoted the gen by parg DNA om 1077 gay and 1231 straight men. Intertgly, this bra regn ntas the hypothalam, which was intified 1991 as differg size between gay and straight men.
Grave’s disease is more mon gay than straight men, and some rearch suggts that gay men tend to be thner – which might possibly be a rult of thyroid overdrive.
IS THERE A "GAY GENE"? MAJOR NEW STUDY SAYS NO
“There will be men who have the form of gene that creas the chance of beg gay, but they won’t be gay. There have been studi suggtg that there is a geic element to homosexualy women, but more rearch has been done men, says Sanrs. The latt fdgs open the prospect to intifyg the whole pathway of gen volved both homosexual and heterosexual orientatn, says Dean Hamer at the US Natnal Instut of Health, who led the study that ppoted chromosome X back 1993.
Read more: Evolutn myths: Natural selectn nnot expla homosexualy. Those who nsir beg gay a disadvantage life (which still is, certa societi), might regard gay people differently if they knew that beg gay was an hered tra, rather than a nsequence of life events, such as a particular type of upbrgg, or mixg wh certa sorts of iends or even a liberate cisn.
The law also might take a different view those untri (aga, there are still many) which beg gay is a crimal offense. An early study claimed that if one pair of (male) intil tws (who have intil geic patterns) was gay, there was a 100 percent chance of the other one also beg gay. It was quickly shown that, fact, the real chance of two intil tws beg gay was around 40-50 percent, whereas was ls non-intil on, though still somewhat greater than the general populatn.
IS THERE A “GAY GENE"?
A dramatic claim was that there was a sgle geic variatn, the "gay gene, " that was found gay men.
HOW OUR GEN ULD MAKE GAY OR STRAIGHT
Alas, like so many other early reports of a "gay gene, " this one uld not be repeated. There was another, much smaller, group who said they were entirely gay (about 6 percent), and a stterg of even smaller numbers who claimed to be bisexual. Firstly, they found very few gen whose variatns were rrelated wh beg gay, or even havg a sgle same-sex partner.
Overall, geic variatns acunted for only around 1 percent of the likelihood of beg gay. And beg gay creased the chance of dg e, socially risky behavur and smokg. What term whether someone will be straight or gay, or somewhere between?