But genetically non-binary individuals make up a tiny proportion of the population. To a first approximation, there are two genetic sexes and saying so is a reasonable generalization, even though there are edge cases like Semenya that should be dealt with sensitively.

In aggregate, they make up about ~1% of the population. That’s rare, but common enough that you probably know a few. It is far more common than was once thought because of the prevalence now of genetic testing. Before XXX or XXY would have gone undiagnosed, for example.

From one of the article's sources on "1.7%":

> Specifically, Fausto-Sterling computes the incidence of intersexual births to be 1.7 per 100 live births, or 1.7%. To arrive at that figure, she defines as intersex any “individual who deviates from the Platonic ideal of physical dimorphism at the chromosomal, genital, gonadal, or hormonal levels”

So someone with elevated estrogen but normally functioning male genitalia and XY chromosomes would be part of this 1.7%, as might an effeminate looking man or a boyish female.

I rather suspect that is not what most people would assume when reading that number.

Well that's not how I arrived at the 1% number. Look at the underlying frequencies of the genetic abnormalities.

The article's author did, and came up with a number about 2 orders of magnitude lower.

thanks for the link, it's very interesting. My next question (in general, not to you) would be to know how these people with the other combinations are classified by the sports organizations. It seems like a really complex issue, and to form an opinion one needs to really get into the nuances. I think the press pushing the narrative that women are discriminated against without at least a mention of the nuances involved is a bit irresponsible. The discussion here might help some folks to form a more informed opinion.

AFAICT this ruling basically only applies to XY women with high testosterone levels. XXY men (who would have low T levels) still compete against other men, and XXX women (with less than typical T levels even for women) compete with other women. There are many other variations though, but I do’t know any other than XY(f.) which would endanger gender separation in sports.

Note that trans women (m->f) get to compete with other women. That’s part of the unfairness here. A male athlete can surgically make their body female and be allowed to compete, but Caster Semenya who was born essentially the same way is blocked from competing.

> Note that trans women (m->f) get to compete with other women. That’s part of the unfairness here. A male athlete can surgically make their body female and be allowed to compete, but Caster Semenya who was born essentially the same way is blocked from competing.

It’s not just surgically. Athletes are required to reduce their testosterone levels, which is the issue here.