I’m still reading the new Julia Serano book, Excluded, which is very impressive. Part of the reason why Serano is so good on gender issues is that she’s an actual biologist — a proper scientist, not someone who uses a few scientific ideas to advance a political theory. So when she writes about biological aspects of gender she does so from the point of view of skeptical inquiry, rather than from faith in a grossly simplified distortion of science, or faith in the evil of science, as we generally see in such discussions.

Some of you may remember that when I was researching Michael Dillon I came across a condition called hypospadias. People with this condition are often assigned female at birth despite being chromosomally male. Back at the beginning of the 20th Century many doctors were aware of the problem, and would happily write a letter to the authorities asking that a person with hypospadias be re-assigned as male. I suspect that the surgeon who performed Dillon’s top surgery used this as a cover for getting Dillon’s gender re-assigned, even though he did not have hypospadias.

Well one of the chapters of Excluded that I have just read mentioned a related condition, cloacal exstrophy. The reason that Serano mentions is is that she knows of a follow-up study of 14 people with this condition, all of whom had been raised female. By adolescence 8 of them had declared themselves to be male, despite having no knowledge of their male chromosomes. All of them, regardless of how they identified, were reported by the researchers as exhibiting male-typical behavior.

Part of the reason why this resonated so strongly with me is that yesterday The Independent ran an article about intersex people who have the condition known as androgen insensitivity syndrome. This is another condition whereby people with male chromosomes are assigned female at birth, and yet people with this condition typically are very happy being raised female and continue to identify as such. Many are distraught to discover, as adults, that they are infertile.

So there we have two groups of people, both with male chromosomes, both liable to be assigned female at birth. And yet one group mostly grows up to adopt male gender behavior and identity, while the other group mostly grows up to adopt female gender behavior and identity. Mostly, but not all, because our biology is amazingly complex. The idea of master control switches that turn certain behaviors on and off is a gross simplification.

And yet we still have people who claim that science “proves” that anyone with XY chromosomes is “really” a man. *sigh*