No ‘gay gene’: Massive study hom on geic basis of human sexualy

gay genetics research

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

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SEARCH FOR 'GAY GEN' COM UP SHORT IN LARGE NEW STUDY

The gay gene was first intified 1993 as a rrelatn between the geic marker Xq28 and gay male sexualy. The rults of this origal study were never replited, and the blogil realy of such an enty remas hypothetil. However, spe such tenuo provenance, the gay gene has p … * gay genetics research *

And bee the rearchers didn't fd gene variants that rrelated wh a gradient of sexual behavr, she says, unrcuts Aled Ksey's s-old sle, which ranked people on a spectm of sexualy, om exclively heterosexual to exclively homosexual.

THERE IS NO ‘GAY GENE.’ THERE IS NO ‘STRAIGHT GENE.’ SEXUALY IS JT PLEX, STUDY NFIRMS

* gay genetics research *

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.

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. “[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. However, spe such tenuo provenance, the gay gene has persisted as a reference science news, popular science wrgs, and prs releas and edorials about bmedil rearch.

News media monstrat that the gay gene has bee an assumed back-story to geic sexualy rearch over time, and that the crique of s very existence has been dimished.

THE LIFE OF THE GAY GENE: OM HYPOTHETIL GEIC MARKER TO SOCIAL REALY

The nsequent unmoorg of the gay gene om acuntabily and accuracy monstrat that the anizatn of bmedil databas uld benef om greater cross-disciplary attentn.

In theory, humans and other animals who are exclively attracted to others of the same sex should be unlikely to produce many blogil children, so any gen that predispose people to homosexualy would rarely be passed on to future generatns.

Yet same-sex attractn is wispread humans, and rearch suggts that is partly a study of data om hundreds of thoands of people, rearchers have now intified geic patterns that uld be associated wh homosexual behavur, and showed how the might also help people to fd different-sex mat, and reproduce. The thors say their fdgs, published on 23 Augt Nature Human Behavur1, uld help to expla why gen that predispose people to homosexualy ntue to be passed down. Most of the participants were born durg a time when homosexualy was eher illegal or culturally taboo their untri, so many people who were attracted to others of the same sex might never have actually acted on their attractn, and uld therefore have end up the wrong group the Monk, an elogist and evolutnary blogist at Yale Universy New Haven, Connecticut, thks that the veats are so important that the paper n’t draw any real nclns about geics and sexual orientatn.

NO ‘GAY GENE’: MASSIVE STUDY HOM ON GEIC BASIS OF HUMAN SEXUALY

Instead, he thks the rearchers have found geic markers associated wh openns to new experienc, which uld expla the overlap between people who have had a homosexual partner and heterosexual people who have had many partners.

And he adms that g a sgle homosexual experience as an ditn of sexual orientatn isn’t ial, but says that the UK Bbank didn’t provi data on attractn. “There is no ‘gay gene’, ” says lead study thor Andrea Ganna, a geicist at the Broad Instute of MIT and Harvard Cambridge, and his lleagu also ed the analysis to timate that up to 25% of sexual behavur n be explaed by geics, wh the rt fluenced by environmental and cultural factors — a figure siar to the fdgs of smaller studi. 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.

REARCH NFIRMS 'GAY GENE' DISVERY

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.

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. They asked more than 477, 000 participants whether they had ever had sex wh someone of the same sex, and also qutns about sexual fantasi and the gree to which they intified as gay or straight. “A lot of people want to unrstand the blogy of homosexualy, and science has lagged behd that human tert, ” says William Rice, an evolutnary geicist at the Universy of California, Santa Barbara, who also was not volved the work.

For ee real time breakg news alerts sent straight to your box sign up to our breakg news emailsSign up to our ee breakg news emailsThe scientist who two years ago ntroversially announced the disvery of the "gay gene" has found further evince for s existence homosexual men but not lbian Hamer, a geicist at the US Natnal Cancer Instute Washgton DC, said yterday that his latt rearch nfounds the crics who lled his earlier work to qutn.

'GAY GEN': SCIENCE IS ON THE RIGHT TRACK, WE'RE BORN THIS WAY. LET’S AL WH .

A proclivy for homosexualy which some men rry on the X chromosome they her om their mothers is nfirmed by the latt work, published Nature Geics, Dr Hamer said.

WHAT DO THE NEW ‘GAY GEN’ TELL ABOUT SEXUAL ORIENTATN?

"Dr Hamer, workg this time wh a team om the Universy of Colorado and the Whehead Instute Cambridge, Massachetts, extend his earlier study of gay brothers to clu heterosexual brothers and lbian sisters. He reproduced the rults of the earlier work by fdg that geic tras on a regn of the X chromosome were more likely to be shared by gay men, suggtg this part of the chromosome is volved sexual Dr Hamer said was far om certa that any man who hers the "gay gene" will bee homosexual.

Fdg evince for a blogil basis should not sre or unrme gay, lbian and bisexual (LGB) rights (the studi I refer to do not clu transgenred dividuals, so I’ll nfe my ments to lbian, gay and bisexual people).

THERE’S (STILL) NO GAY GENE

Evince om pennt rearch groups who studied tws shows that geic factors expla about 25-30% of the differenc between people sexual orientatn (heterosexual, gay, lbian, and bisexual). Three gene fdg studi showed that gay brothers share geic markers on the X chromosome; the most recent study also found shared markers on chromosome 8.

CONTROVERSIAL ‘GAY GENE’ APP PROVOK FEARS OF A GEIC WILD WT

Gen uld themselv nudge one towards a particular sexual orientatn or gen may simply teract wh other environmental factors (such as sex hormon the womb environment) to fluence later sexual bras of gay and heterosexual people also appear to be anised differently.

The fluence of blogy ns throughout our sexual and genred liv and those differenc, that diversy, is surely to be wrers tend to wave off the scientific evince by urgg to look to the history of sexualy or claim that homosexualy is a social nstctn (cue Michel Fouult and the like). Surely our choic are the rult of thgs we didn’t choose (our gen, personali, upbrgg, and culture) worry that scientific rearch will lead to “cur” for homosexualy (which is an odd worry to have if you don’t believe the “born this way” argument). We are who we are, and our sexuali are part of human worry about the claims of social nstctn, choice and such like is that plays to the hands of homophobic iology, to the hands of the “aversn therapists”, and to the hands of a growg culture which seeks to mimise gay differenc.

THERE’S NO ONE ‘GAY GENE,’ BUT GEICS ARE LKED TO SAME-SEX BEHAVR, NEW STUDY SAYS

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. 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.

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. There is no one gene for beg gay, and though gen seem to play a role termg sexual orientatn and same-sex behavr, ’s small, plex, and anythg but termistic. “We know that smell has a strong tie to sexual attractn, but s lks to sexual behavrs are not clear, ” said -thor Andrea Ganna, an stctor at HMS and Massachetts General Hospal om the Instute for Molecular Medice study is part a rponse to gay, lbian, and bisexual people’s cursy about themselv, said Fah Sathirapongsasuti, a senr scientist at 23andMe and -thor on the study, who is himself gay.

GAY GEICSMOST OF BELIEVE THAT WE WERE BORN THAT WAY, BUT IS SEXUAL ORIENTATN OUR DNA? JV CHAMARY GO SEARCH OF THE GAY GENEJV CHAMARYPUBLISHED: MAY 31, 2009 AT 11:00 PMGAY GEICS

Michael Bronski, profsor of the practice media and activism wh the mtee on studi of women, genr, and sexualy, and thor of A Queer History of the Uned Stat, says the allure of a “gay gene” grew om the flourishg gay-rights movement the after the Stonewall rts 1969.

MANY GEN INFLUENCE SAME-SEX SEXUALY, NOT A SGLE ‘GAY GENE’

Conservative opponents of the movement claimed that “homosexual acts are a choice, people choose to m them, or people are sced to the gay liftyle, ” he explas. ’77, then a rearcher at the Natnal Instut of Health, published rults showg a rrelatn between male homosexual behavr and a clter of gen, lled Xq28, at the tip of the X chromosome. Exactly which gene this clter may be volved has proven elive—the current study found no signifint associatn between the X chromosome and same-sex sexual behavr—but the ia that a “gay gene” might lie somewhere Xq28—or elsewhere—was ptivatg.

Zeke Stok, chief programs officer of the LGBTQ advocy anizatn GLAAD, ncurred an emailed statement: “This new study provis even more evince that beg gay or lbian is a natural part of human life, a ncln that has been drawn by rearchers and scientists time and aga. Others have warned that the search for a geic e would pathologize homosexualy the same way psychology did the twentieth century: efforts by psychoanalysts such as Irvg Bieber led to the cln of homosexualy the Amerin Psychiatric Associatn’s Diagnostic and Statistil Manual of Mental Disorrs until 1972.

BEG GAY NOT A CHOICE: SCIENCE CONTRADICTS BEN CARSON

As noted above, the gen that rrelated wh same-sex sexual behavr also rrelated wh willgns to take risks, a nnectn that might not hold up cultur where homosexualy is ls stigmatized and those who are ls risk tolerant would therefore feel more able to act openly. The rearchers say that, although variatns the gen nnot predict whether a person is gay, the variants may partly fluence sexual Ganna, lead thor and European Molecular Blogy Laboratory group lear at the Instute of Molecular Medice Fland, said the rearch rerc the unrstandg that same-sex sexual behavr is simply “a natural part of our diversy as a speci. Some of the variants were rrelated wh same-sex sexual behavr men, others women, and some Vila, director of the Center for Geic Medice Rearch at Children’s Natnal Health System, said the study marks the end of “the simplistic ncept of the ‘gay gene.

Environmental effects may be a factor for some people; for stance, havg olr brothers creas the odds that younger brothers will be gay, which rearchers spect may have to do wh chang to the mother’s immune system rponse to the earlier Stok, chief programs officer for GLAAD, said a statement that the new rearch on the geics “provis even more evince that beg gay or lbian is a natural part of human life, a ncln that has been drawn by rearchers and scientists time and aga. This new rearch also renfirms the long tablished unrstandg that there is no nclive gree to which nature or nurture fluence how a gay or lbian person behav.

THE 'GAY GENE' IS A MYTH BUT BEG GAY IS 'NATURAL,' SAY SCIENTISTS

“Conservative, right-wg people hated bee they felt that was sayg that beg gay is like beg black, that was -born, that would somehow ‘exce’ gay people or give them more rights, ” says Hamer. “On the other hand, gay people hated too bee, at that time, there were fears that the disvery would be mised to abort gay babi and wipe gay people off the face of the Earth.

Although the fears rema, recent years the search for ‘gay gen’ has bee more accepted by the gay muny, no small part bee a blogil explanatn wouldunrme arguments that beg gay is a social or liftyle choice.

For stance, intil tw brothers (siblgs rived om the same fertilised egg) are more likely to both be gay than aternal tws (tws that velop om separate eggs). Now chief of the gene stcture and regulatn sectn at the US Natnal Cancer Instute, his study revealed a cur pattern: gay men tend to have more gay uncl and gay male s on their mother’s si of the fay than on their father’s. To track down the DNA regn lked to the gay tra, Hamer ed a technique lled ‘lkage mappg’, an approach that lets geicists fd a gene even when they don’t know what do or where ’s loted.

IS THERE A "GAY GENE"? MAJOR NEW STUDY SAYS NO

The exceptn is homosexual men’s bras, which show remarkable siari to the bras of heterosexual women, suggtg that sexual orientatn pends on the effect hormon have on the velopg bra. In 1996 Blanchard and Profsor Tony Bogaert revealed a peculiar phenomenon: the more olr brothers a boy has, the greater their chanc of beg homosexual.

HOW EARNT REARCH INTO GAY GEICS WENT WRONG

Blanchard believ that homosexualy is “100 per cent blogil”, and timat that the aternal birth orr effect acunts for 15-30 per cent of gay men the populatn. Not only did he replite Blanchard’s birth orr effect, he also tected herance of homosexualy on the mother’s si, supportg Hamer’s ia of a gay gene on chromosome X. Natural selectn oppos anythg that might e even a small rctn the number of offsprg you produce, so a gay tra would soon disappear om the gene pool.

After Camper Ciani scribed the observed patterns pedigre of homosexualy – the effects of maternal herance and birth orr – his dghter suggted that he re-check his data to see if the female relativ of gay men had more children on the mother’s si.

“Mothers and nts on the maternal le of homosexuals had around one-fifth to one-fourth more kids than the heterosexual parison, and also than the paternal le. “People we talked to at gay pri ftivals have signer-baby kd of worri – a geic tt employed a pre-natal way, or for employment and surance discrimatn, maybe the ary too.

SCIENTISTS QUASH IA OF SGLE 'GAY GENE'

Muny there said they were worried the fdgs uld give ammunn to people who seek to e science to bolster bias and discrimatn agast gay ncern is that evince that gen fluence same-sex behavr uld e anti-gay activists to ll for gene edg or embryo selectn, even if that would be technilly impossible.

Another fear is that evince that gen play only a partial role uld emboln people who sist beg gay is a choice and who advote tactics like nversn therapy.

Dpe s limatns, the rearch was much larger and more varied than prev studi, which generally foced on gay men, often those who were tws or were otherwise related. “That right there is the big issue wh lookg for the geics of sexual orientatn — social ntext uld be a big part of the exprsn of the tra, ” said Jeremy Yor, an assistant profsor of blogy at California State Universy, Northridge, who is gay and follows geic rearch the field. He and others noted that olr participants me of age when homosexual behavr was crimalized Bra and that for much of their life homosexualy was classified as a psychiatric Reilly and others said such stark differenc between olr and younger participants show the tricks of tryg to draw reprentative blogil rmatn om a study populatn so strongly fluenced by society’s changg attus.

*BEAR-MAGAZINE.COM* GAY GENETICS RESEARCH

The 'Gay Gene' Is A Myth But Beg Gay Is 'Natural,' Say Scientists .

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