there’s been some buzz recently about a caster semenya, an 18-year-old south african runner who may be asked to undergo “gender testing” after she “burst onto the scene by improving her personal bests in the 800 and 1,500 by huge margins.” (espn) putting aside the issue of whether semenya’s times indicate a problem, i was extremely curious as to what happened in a gender test. what do they do? how do they decide?
even when they were first introduced by the international olympic committe (IOC) in 1968 as a response to increasing use of anabolic steroids, the tests were seen as intrusive and humiliating. this is because initial tests were simply physical examinations, where doctors would poke and prod at genitals.
later, the IOC switched to a chromosomal test, which can be done with mouth scrapings: two X chromosomes meaning female, and XY meaning male. but “the method proved to be unreliable, since it’s possible for a biological male to have an extra X chromosome (XXY) or a female to only have one X chromosome.” according to some estimates, these chromosomal abnormalities occur as often as 1 in 1,000 people.
the next step was a blood test to determine the presence of SRY, a gene on the Y chromosome that instructs the developing fetus to activate the gonads to develop into testes instead of ovaries, and to produce two hormones to develop male sex organs and destroy what would turn into female sex organs. if the SRY gene is present, the doctor checks to make sure it’s functional and not mutated or disabled.
however, “the SRY trigger isn’t the only factor in developing maleness, and even cells with a working SRY gene can end up living in the body of a functioning female. A dysfunction in any of the many later stages of male-female development, triggered by a number of other genes that play a specific role in gender distinction from the womb through adolescence, can affect the genetic, chromosomal and physical traits that any man or woman possesses.” [edited to note this is quoted language, i would prefer “even a person with functioning female sex organs who identifies as female can have cells with a working SRY gene.”] so even a positive finding of a functioning SRY gene is insufficient to conclusively determine gender.
there’s additional problems when these tests come up with conflicting results - external genitalia indicates female, but there’s a Y chromosome with a slightly altered SRY gene. and it’s unclear how gender identity fits into this, or whether it matters at all as what gender the person has been identifying.
there’s a great simulator available where you can step through the gender testing of a hypothetical athelete and decide how you’re going to reconcile conflicting test results. (it also gives much more detailed info on the SRY testing, etc.) i found it very interesting to see what determined my judgment was primarily that the athelete had self-identified as female, while another friend reached the same judgment because going with external genitalia made the most sense to him. yet another friend really struggled with the idea that there wasn’t a single test or factor that would conclusively indicate male or female.
for me, the lack of any 100% clear non-conflicting blood test does a lot to reinforce my ideas about the non-binary nature of gender and even sex. sure, most people will fit into male or female pretty well - i imagine if i ran these tests on myself, they would all agree that i’m female without any conflicts - but there are a significant number around the edges which challenge the idea of fixed binary categories.
[edited to add: this does not address the issue of transgender individuals at all. there are specific IOC rules for athletes who have undergone sexual reassignment surgery, but they are distinct from these gender testing rules applied to cis-athletes.]