If common sense isn’t significant proof that being trans isn’t a choice, perhaps the science will be.
First off, an admission: there isn’t a giant body of research on trans people. We are relatively rare individuals in the first place. To worsen things, stigmatization of our community makes us a less approachable subject of study for most cis folk. Research is often profit-driven in corporate US, and trans people don’t bring in nearly the revenue that, say, epinephrine pens do. The research that is out there tends to lean towards social and psychological studies, rather than the biology. Plenty of people with no authentic scientific backgrounds pontificate about us, often opining that being trans is a choice. Actual published, double-blind, peer-reviewed scientific or medical literature still leaves plenty of room for growth, to say the least.
Limitations aside, there is some real research out there. I will first discuss some of the theories about the possible causes of variance in gender and gender identity. Harder biological evidence, however, is found in brain studies comparing trans people’s brains to cis people’s brains. While I give strong weight to the personal experiences of countless of trans and non-binary individuals in their self-affirmations, I explore this from my own personal point of view in the final column in this series.
Why Are People Born Transgender, Non-Binary, etc?
Bottom line is, we don’t know entirely. Finding a specific gene or measuring intra-uterine hormone levels throughout gestation present some problems. We do have some very strong hints, however.
Genetic: no specific ‘gay’ gene’ or ‘trans gene’ has been discovered yet. Many in the trans community hope this will never happen, as it could become a test of trans-ness, and geez, don’t we have enough of that within our community without encouraging those outside to pathologize or categorize us even more? Some may wonder, if I don’t have the gene, am I still really trans? Will I be de-legitimized even further?
Nonsense. Trans, non-binary, any gender identity, even cis, is self-identified, first and foremost. Not even delving into the complexities of gender, gender roles, and society, much of which are cultural and a lot less ‘set in stone’ than we often think, being trans is about expressing our inner souls, our identities. It’s about being authentic to ourselves, to what is in our hearts, and having the courage to share this with the world. We are, first and foremost, humans. Some identities fit more neatly into whatever arbitrary boxes conventional thinking and the limitations of language may confine us, but who we are, at core, is inviolable, regardless of how able or comfortable we are able to express ourselves at any given time.
This may be the single biggest thing which cis folks get to take for granted which trans and non-binary folk have to struggle with to own: “I yam what I yam and that’s all what I yam!” -Popeye, US sailor and philosopher.
That, however, is a subject for another column altogether. Back to the genes.
While no specific genes have been discovered, scientists have long used another technique to suss out possible genetic components: twin studies.
Identical twins share nearly identical DNA, as opposed to fraternal twins, who share about half their genes. If both sets are raised together, environment is fairly well controlled. So, anything which pops up in identical twins with a statistical significance sufficiently greater than it turns up with fraternal twins likely has a genetic component. Did you notice all the conditional language? Science doesn’t like to commit to anything without piles of evidence. What we have is very strong correlation. Still, it’s significant.
Being gay or being trans occurs more often in both of a pair of identical twins than in fraternal twins, strongly suggesting that some genetic component is in play for some people.
It should be noted that xy fetuses have a gene (SRY) which controls the other sex differentiation genes, like a master switch. Possible alteration of the SRY gene provides a convenient and logical genetic explanation for some expressions of gender variability, but I would caution anyone from taking a “one explanation fits all” model when speaking of biology. Everything in nature is a lot more complex than we usually learn about in public education. There may yet be more than one biological path to being born transgender or non-binary.
Epigenetic Factors: every single human on earth started out as female. For the first few weeks in utero, the fetus is female. At 7 weeks, genitals begin to differentiate. Very small amounts of hormones initiate these changes. If things progress in a non-standard way, the human may develop with some form of intersex genitals, as happens with 1 in 1,000 people. Otherwise, hormones will trigger the fetus to become male or female, at least in their genitals.
Here’s the interesting part: the changes in fetal brain dimorphism (female brain vs. male brain, to over-simplify) happen months later. What if the fetus develops with genitals developing in the direction of one gender, while the brain develops in the direction of the other gender? What if development occurs somewhere on the spectrum between male and female? Everyone develops with natural variety, and this includes how masculine or feminine a person becomes, neglecting the difficulty of what that even means, really. Transgender and non-binary humans are merely the statistical outliers in a natural variety.
For various reasons, both ethical and scientific, this would be very difficult to prove absolutely in humans, but it all fits very neatly with everything we know about how humans develop.
Other animals, on the other hand, fall outside many of the ethical constraints applied to humans. Abnormal hormone levels in prenatal animals have been clearly shown to affect physical and behavioral development of rats in exactly the ways it is theorized happens in people. Hmmm….
Physical Proof That Trans Brains Are Different
Now we get to the really fun stuff. By which I mean much harder evidence.
First note that, really, male and female brains are not that much different, cable channels full of vintage sitcoms notwithstanding. We all, trans, cis, non-binary, women and men, have lots more in common than in difference. As strange as it may seem, a right-wing conservative white man, a Hispanic leftie woman, and an apolitical trans woman of color have much more similar brain structures and functioning, than, say, your average 5 year old.
There are some differences, however. Men tend to have more gray matter, while women tend to have more white matter in their brains. A woman will generally have a larger corpus collosum (the part that connects the brain hemispheres) than a man. There may be differences in the hippocampus and amygdala, as well. Some differences in the prefrontal cortex may exist. We still know little about the brain, and not all is perfectly settled yet.
The Kicker: trans brains are more like the gender they profess, than the brains of the gender they were presumed to be at birth. Transmen have masculine brains, and transwomen have feminine brains, once again, oversimplifying things. Gender exists on a natural spectrum: the very idea of simplistic, black and white categories are more a mental model than anything reflecting the actual variation of human experience. All this is before hormone replacement therapy, which affects the brain even more.
To simplify: as a transwoman, I have a (mostly) female brain, and always have. Hormones have made my brain even more feminine. I certainly chose the hormones, but I did not choose my original brain structure.
Further, trying to live with a female brain in a male body did not work for me. Trying to live socially as a man really didn’t work for me. The personal costs of trying to repress myself are a subject the next post. Suffice it to say that after 40 years of trying to live as the gender everyone thought I was, the gender my body seemed to indicate, the only cure for my being transgender was to transition.
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I AM CAM (she/her)