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How genes and evolution shape gender – and transgender – identity

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How genes and evolution shape gender - and transgender - identity

How genes and evolution shape gender – and transgender – identity

Mismatch between biological sex and gender identity, culminating in its severest form as gender dysphoria, has been ascribed to mental disease, family dysfunction and childhood trauma.

But accumulating evidence now implies biological factors in establishing gender identity, and a role for particular genes.

Variants – subtly different versions – of genes linked with gender identity might simply be part of a spectrum of gender and sexuality maintained throughout human history.

How genes and evolution shape gender - and transgender - identity

Transgender and gender dysphoria

Some young boys show an early preference for dressing and behaving as girls; some young girls are convinced they should be boys.

This apparent mismatch of biological sex and gender identity can lead to severe gender dysphoria. Coupled with school bullying and family rejection, it can make lives a torment for young people, and the rate of suicide is frighteningly high.

As they move into adulthood, nearly half of these children (or even more when the studies are closely interrogated), continue to feel strongly that they were born in the wrong body. Many seek treatment – hormones and surgery – to transition into the sex with which they identify.

Although male to female (MtF) and female to male (FtM) transitions are now much more available and accepted, the road to transition is still fraught with uncertainty and opprobrium.

Transwomen (born male) and transmen (born female) have been a part of society in every culture at every time. Their frequency and visibility is a function of societal mores, and in most societies they have suffered discrimination or worse.

This discrimination stems from a persistent attitude that transgender identification is an aberration of normal sexual development, perhaps exacerbated by events such as trauma or illness.

However, over the last decades, growing recognition emerged that transgender feelings start very early and are very consistent – pointing to a biological basis.

This led to many searches for biological signatures of transsexualism, including reports of differences in sex hormones and claims of brain differences.

How genes and evolution shape gender - and transgender - identity

Sex genes and transgender

In the 1980s I was swayed by the passionate advocacy of Herbert Bower, a psychiatrist who worked with transsexuals in Melbourne. He was revered in the transgender community for his willingness to authorise sex change operations, which were highly controversial at the time. Aged in his 90s, he came to my laboratory in 1988 to explore the possibility that variation in the genes that determine sex could underlie transgender.

Dr Bower wondered if the gene that controls male development might work differently in transgender boys. This gene (called SRY, and which is found on the Y chromosome) triggers the formation of a testis in the embryo; the testis makes hormones and the hormones make the baby male.

There are, indeed, variants of the SRY gene. Some don’t work at all, and babies who have a Y chromosome but a mutant SRY are born female. However, they are not disproportionately transgender. Nor are the many people born with variants of other genes in the sex determining pathway.

After many discussions, Dr Bower agreed that the sex determining gene was probably not directly involved – but the idea of genes affecting sexual identity took root. So are there separate genes that affect gender identity?

Evidence for gene variants in transgender

The search for gene variants that underlie any trait usually starts with twin studies.

There are reports that identical twins are much more likely to be concordant (that is both transgender, or both cisgender) than fraternal twins or siblings. This is probably an underestimation given that one twin may not wish to come out as trans, thus underestimating the concordance. This suggests a substantial genetic component.

More recently, particular genes have been studied in detail in transwomen and transmen. One study looked at associations between being trans and particular variants of some genes in the hormone pathway.

A recent and much larger study assembled samples from 380 transwomen who had, or planned, sex change operations. They looked in fine detail at 12 of the “usual suspects” – genes involved in hormone pathways. They found that transwomen had a high frequency of particular DNA variants of four genes that would alter sex hormone signalling while they had been developing in utero.

There may be many other genes that contribute to a feminine or a masculine sexual identity. They are not necessarily all concerned with sex hormone signalling – some may affect brain function and behaviour.

The next step in exploring this further would be to compare whole genome sequences of cis- and transsexual people. Whole genome epigenetic analyses, looking at the molecules that affect how genes function in the body, might also pick up differences in the action of genes.

It’s probable that many – maybe hundreds – of genes work together to produce a great range of sexual identities.

How genes and evolution shape gender - and transgender - identity

How would “sexual identity genes” work in transgender?

Sexual identity genes don’t have to be on sex chromosomes. So they will not necessarily be “in sync” with having a Y chromosome and an SRY gene. This is in line with observations that gender identity is separable from biological sex.

This means that among both sexes we would expect a spread of more feminine and more masculine identity. That is to say, in the general population of males you would expect to see a range of identities from strongly masculine to more feminine. And among females in the population you would see a range from strongly feminine to more masculine identities. This would be expected to produce transwomen at one end of the distribution, and transmen at the other.

This occurrence of a range of differing identities would be comparable with a trait such as height. Although men are about 14 cm taller than women on average, it’s perfectly normal to see short men and tall women. It’s just part of the normal distribution of a certain human characteristic expressed differently in men and women.

This argument is similar to that which I previously described for so-called “gay genes”. I suggested same–sex attraction can readily be explained by many “male-loving” and “female-loving” variants of mate choice genes that are inherited independently of sex.

Why is transgender so frequent then?

Transgender is not rare (MtF of 1/200, FtM of 1/400). If gender identity is strongly influenced by genes, this leads to questions about why it is maintained in the population if transmen and transwomen have fewer children.

I suggest genes that influence sexual identity are positively selected in the other sex. Feminine women and masculine men may partner earlier and have more kids, to whom they pass on their gender identity gene variants. Looking at whether the female relatives of transwomen, and the male relatives of transmen, have more children than average, would test this hypothesis.

I made much the same argument to explain why homosexuality is so common, although gay men have fewer children than average. I suggested gay men share their “male loving” gene variants with their female relatives, who mate earlier and pass this gene variant on to more children. And it turns out that the female relatives of gay men do have more children.

These variants of sexual identity and behaviour may therefore be considered examples of what we call “sexual antagonism”, in which a gene variant has different selective values in men and women. It makes for the amazing variety of human sexual behaviours that we are beginning to recognise.The Conversation

Jenny Graves, Distinguished Professor of Genetics, La Trobe University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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‘Game of Thrones’ star Sophie Turner: “I love a soul, not a gender”

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'Game of Thrones' star Sophie Turner: "I love a soul, not a gender"
HBO

Sophie Turner, known for her roles as Sansa Stark on Game of Thrones and Jean Grey in the X-Men movies (including this year’s Dark Phoenix), spoke about love in a recent interview with Rolling Stone.

More specifically, in the article, which focuses on her and GoT co-star Maisie WilliamsGrowing Up Game of Thrones,” Turner spoke about the way she loves. She revealed that she “never thought she’d get engaged so young, or at all,” adding, “I was fully preparing myself to be single for the rest of my life.” She is currently engaged to singer Joe Jonas.

Related | Little Mix sings under massive rainbow flag during performance in Dubai

She goes on to say that she believes her soul to be much older than her age (22, in case you’re wondering) and that she’s “lived enough life to know” when she’s found the person she wants to be with.

“I’ve met enough guys to know — I’ve met enough girls to know. I don’t feel 22. I feel like 27, 28.” When pushed to elaborate on the “girls” part, Turner continued. “Everyone experiments. It’s part of growing up. I love a soul, not a gender.”

Turner didn’t label her sexuality one way or another.

'Game of Thrones' star Sophie Turner: "I love a soul, not a gender"

The final season of Game of Thrones premieres April 14 and Dark Phoenix hits theatres June 7, 2019.

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Just 55% of Americans believe LGBTQ people “face a lot of discrimination”

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Just 55% of Americans believe LGBTQ people face a lot of discrimination

With rising support for marriage equality and the LGBTQ community comes a bit of a distorted view on the issues of discrimination those within the community still face.

According to a new report from FiveThirtyEight, “only 55 percent of Americans believe that gay and lesbian people face a lot of discrimination in the U.S., down from 68 percent in 2013.”

But those numbers may be skewed, depending on how the person responding is surveyed. According to the same article, a 2014 report “found that Americans were 14 points less likely to say gays and lesbians experience a lot of discrimination when responding to an online survey than when a pollster called them.”

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What’s more, an increasing number of Americans seem to be believing the idea that fighting for LGBTQ rights is largely unnecessary. A 2017 Gallup survey found that 46 percent of people do not think “news (sic) civil rights laws are needed to reduce discrimination against lesbian, gay, bisexual or transgender people.” A 2018 survey from PRRI revealed that 49 percent believe the U.S. “has made the changes needed to give gay and lesbian people equal fights with other Americans.”

It’s nice that people believe LGBT citizens have been given the rights to make them equal with other Americans, but it’s simply not the case, especially when you consider that new rights don’t always mean increased acceptance. In fact, anti-LGBTQ hate crimes rose 3 percent in 2017, according to the FBI. Of the 1,470 victims who “were involved in 1,249 separate bias incidents,” close to 60 percent were against gay men and 25 percent were against “a mix of LGBTQ people.”

The number of hate crimes in the U.S. against those in the LGBTQ community has increased every year since 2014.

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Bill Tamlyn is the gay Instagram daddy you need to follow

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Bill Tamlyn is the gay Instagram daddy you need to follow

Bill Tamlyn is many things: a father, a model, and a certifiable Instagram daaaaaddy. In terms of shirtless men, he ranks up there with the best of them.

The 52-year-old single-dad from Minneapolis, Minnesota, who boasts over 29,000 followers on his Instagram account, told Gay Star News in an interview last year that “he juggles fatherhood with a demanding modeling career” and hits the gym almost every day.

Related | 19 adorable photos of @dadsnotdaddies, Instagram’s hottest parents

With regards to his sons, he said, “For all I’ve taught them, I feel like they’ve taught me even more.”

Excuse me while I soothe my non-existent ovaries.

Here are a bunch of his best and most thirst-trap-worthy Instagram photos:

View this post on Instagram

Got your back // 📷 by @nich_thomas

A post shared by BILL TAMLYN (@billtamlyn) on

I think I can speak for everyone.

Bill Tamlyn is the gay Instagram daddy you need to follow

Related | 12 hottest men on Instagram for you to drool over all day long

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