For some reason, political debates concerning LGBT rights and issues like same-sex marriage often end up getting caught up in the question of whether or not being gay, lesbian, bi or trans is a choice. I’ve always considered this to be something of a red herring. Why, exactly, does it matter? If it were a choice, is there anything to justify treating it as anything other than a choice someone has the right to make? Any reason other than “Because The Bible!”, that is?

It’s certainly an interesting question, though. What exactly does cause variance in sexual orientation, gender identity and gender expression? Why do these traits seem to be so fixed and innate? Why are they so unresponsive to attempts at re-conditioning and reparative therapy, even when the individuals involved are genuinely committed and would give anything to be “normal”? And of course there are tons of important medical and bioethical considerations when dealing with transsexuality, which requires medical intervention. If it’s a choice, then those treatments can theoretically be considered elective or cosmetic, but if it’s an innate characteristic, then they’re medically necessary and deserve to be covered by insurance or national healthcare. That particular issue becomes pretty controversial when conversations come up in the trans community over whether or not Gender Identity Disorder should be removed from the DSM.

The hypothesis that most people in the LGBT community run with these days is that it’s some kind of inborn facet of our neurological wiring, rather than a psychological issue or socially constructed predisposition. A simplified version of the theory runs something like this: in utero, prenatal hormones are sort of washed over the developing fetus, and these help steer the child, both physically as well as mentally, towards one sex or the other. The different sexes needed to evolve some differing behavioural characteristics as well as physical ones in order for our whole sexual reproduction thing to work out. As a very basic example, the females needed to mostly be attracted to the males, and the males needed to mostly be attracted to the females. There are all kinds of other behavioural differences too, but I’m usually pretty uncomfortable getting into evolutionary psychology applied towards gender. People always seem way too quick to use it to justify 1950s gender roles or hard gender-essentialism, so I’ll just leave it at the basics. Anyway, we suppose this prenatal hormone thing doesn’t always go quite to plan, and sometimes certain cross-sex neurological or behavioural differences can be triggered without any noticeable physical changes occurring. Perhaps our brains, being as complicated and subtle as they are, are more likely to manifest noticeable differences from subtle changes than other organs and tissues? Chaos theory complicated systems single variables butterflies and hurricanes somethingsomething?

The theory is appealing for a lot of reasons. For one thing, there are the political, ethical and medical considerations above. But it also speaks to and matches our personal experiences of being gay, bi or transgender… that these things are a deep, innate, unchangeable aspect of who we are. Something we never chose, that we usually didn’t want (even if eventually we learned to accept ourselves or even embrace those aspects of our identity), and that feels like it was always there (even if we’re sometimes the last to really know). It’s a belief that meets our social, personal, political and cultural needs, and a belief that feels true.

But as a skeptic, I can’t simply believe something because it feels true, or because it’s convenient to do so. What is the actual science? Is there any hard evidence to support this theory?

Unfortunately, not quite yet. We’re getting there, bit by bit, and certainly a lot of good research is being conducted. But nothing really conclusive has yet come around. You might hear people mention David Reimer, the boy who lost his penis during a botched circumcision and was raised as a girl while his identical twin was raised as a boy. Reimer proved extremely resistant to the efforts to socialize him as female (which were more than a tad unethical… see As Nature Made Him by John Colaptino for the story), and he ultimately chose to live as male. Tragically, he eventually took his own life a few years after his story became public. You might say this provides a strong case for the argument that gender identity is an innate characteristic that can’t be socially reconditioned. His experiences growing up in the “wrong” gender also ring profoundly true for many transgender people. But one case can’t provide a scientific conclusion. There are too many possibilities, too many variables to isolate the actual causal factor. Like perhaps it was the unusual ways in which they attempted to condition him as female that failed, not the concept itself. I don’t really buy the idea that gender identity is a social construct and can be conditioned, but I can’t write it off based on one man’s story, either.

You might also occasionally hear people describe correlations between finger length ratios and sexual orientation, and how this ratio has been conclusively linked to prenatal hormones. But that’s a correlation, not a causal relationship, and there are many people of every possible combination of sexual orientation, physical sex and gender identity who exhibit ratios that contradict the theory. I’m a straight (androphillic) trans woman who exhibits the straight (gynephillic) male ratio myself. I also tested with exceptional spatial reasoning skills! How incredibly macho of me. I guess I lose some tranny-cred, a few points on the COGIATI and my eligibility for “Harry Benjamin Syndrome”. Shucks. But so what? I think the aspects of my self and experiences that directly relate to my gender and orientation speak a lot louder than any random variables that happen to correlate more strongly with one sex or orientation than another.

I’ve been following a series of recent studies out of Stockholm, mostly involving Dr. Ivanka Savic, that have been using magnetic resonance imaging to study sexual dimorphism in the brains of gay men and trans women. There are several ways in which the brains of neurotypical cisgender men and women are noticeably dimorphic, such as hemispheric asymmetry. Men, for instance, display a slight asymmetry between the two hemispheres, with the left being slightly larger than the right. Women display more balance between the two hemispheres. Please, for the love of all that is good, do not take this as proof that men are more rational than women.

This particular study ended up showing that the brains of 48 trans women studied (all of whom were gynephillic- lesbian, and all of whom had not yet begun hormone replacement therapy), did not show the sexually dimorphic features of the cis female sample, but instead more closely resembled the brains of the 48 heterosexual cis men who participated. A few unique features were observed in areas that suggest possible links to things like olfactory sense and body perception.

There were some limitations to the study’s scope, however. For one thing, the sample of trans women were, as noted, entirely lesbian. This makes a lot of good scientific sense on the face of it. A previous study had shown some “female-like” dimorphism in the brains of gay men and it was necessary to control for that, eliminate sexual orientation as a variable and make sure what was being observed were dimorphic characteristics associated only with gender identity. That’s absolutely a good instinct. I’m just not sure they went far enough with it.

Although it seems to have been corrected in the abstract, on my initial reading I noticed that the study confusingly (and somewhat offensively) described the trans lesbian participants as “non-homosexual transsexuals”… and cited the somewhat loathed and discredited author of The Man Who Would Be Queen, and one of my impersonal intellectual arch-nemeses, Jay Michael Bailey, in the process. These are women who are sexually attracted to other women. How exactly is that “non-homosexual”? Rawr! This was the first thing that had me questioning whether the researchers were looking at this the right way and what biases might be in play. Given the earlier studies on how sexual orientation relates to this, and our knowledge that gender identity and sexual orientation do not have a strong or deterministic relationship (if I had a nickel for every time I came across the misunderstanding that trans women are just really, really, really gay, I could probably afford facial feminization surgery), wouldn’t this be a hint that maybe we’re looking for the answers in the wrong place? That the particular dimorphism we’re expecting is a matter of orientation and not identity? And wouldn’t the exclusion of straight trans women from the study be sort of deliberately excluding the group most likely to exhibit the hypothesized “feminine” brains? Why compare trans lesbians to straight cis women instead of lesbian cis women? Doesn’t that rely on the assumption that trans lesbians are “non-homosexual” in order to really make sense? How do we know that what the study didn’t actually prove was just that the brains of trans lesbians resemble those of cis lesbians?

To be honest, although this study does an excellent job of indicating the issues involved are far more complex than simply a case of female brains housed in male bodies, I’m just not sure these kinds of set-ups can provide truly reliable answers unless all possible angles are explored. Rather than question whether the brains of trans lesbians resemble those of straight cis guys or straight cis women, why not also include cis lesbians and cis gay men? Then see which of those four groups the MRIs most closely corresponded to? And also note the various unique differences amongst the groups? This could actually teach us a lot about gender in general, not just trans women. Why not also include straight trans women and see whether their brains more closely matched gay cis men, straight cis men, straight women or lesbians? Why not additionally compare the brains of the trans lesbians to bisexual and straight trans women? Why not include trans men?

Yeah, I know that’s asking a lot, and it’s probably absurd to imagine anyone coming up with enough participants for such a study. It’s hard enough just finding a reasonable sample size of pre-everything gynephillic trans women (there’s not very many of us trans women in general… even the most liberal estimates place us at only around 1 in 2000 people). Having to double or triple that sample to account for other orientations, and having to take on the additional task of finding sufficient gay and lesbian participants, makes it incredibly hard. It would be a massive undertaking, and would seemingly require the entire Stockholm pride parade. But until truly rigorous studies start coming in, the questions still look vague and fuzzy, and we’re still not that much closer to understanding the origins of sexual orientation or gender identity, and we’re still stuck with the religious right condemning our sinful choice of lifestyle, still stuck with having no conclusive arguments to back up our claims of a biological or neurological origin, and those of us with a skeptical bend still end up feeling kind of dirty and ashamed whenever we find ourselves lured into this debate and get caught up in ferociously defending an unproven, albeit very appealing and reasonable, theory.

So what do we do in the mean time, while we sit around waiting for an actual answer to this question? Well, for one thing, we can respond to the “it’s a choice!” argument by saying “Even so, it would be our choice to make, not yours”. And we can listen to some Lady Gaga.

Edited to add some pretty pictures.