Scientists just discovered a woman who's with blood cells that are all XY. Is she a he?
I apologise for coming back to this yet again, but the sheer obtuseness of the question fascinates me. This person is stated to be a woman. So, on what grounds has she been classified as "woman", if not on the basis of her chromosomes? It would seem, on the same grounds as all women are classified as women, by having a female body. The statement is circular, in that it assumes some other way to classify woman or man which is not XX/XY, and then asks us, but is this other way wrong?
No, it isn't. We all know what a woman is, and that some of them do indeed have XY chromosomes. What was your point again, caller?
It's often at this point that the TRAs will trot out a couple of their favourite papers about weird DSDs. One is a study of several members of a family which is notable for throwing up strange anomalies in this department. (One wonders how inbred they are, going back.) The striking thing about the paper is that the authors are in no doubt about who is a woman and who is a man. Their interest is purely in the bizarre genetics. They are not saying, this person who has given birth to a couple of children is not a woman! Merely that this woman has a very strange cellular makeup. It's simply the TRAs who have run with this notion that these obviously phenotypically male or female people aren't male or female because of atypical X and Y chromosome complements.
The other paper is about a single individual, a man who I believe had fathered children, who was discovered to have some ovarian tissue. Only the abstract is available, but there are some strange claims there. First there is the claim that this tissue showed signs of having ovulated. Frankly I don't believe them. You need a complex, highly regulated endocrine system for that to occur, a female one, and a male doesn't have that. Second, they claimed that this person could potentially have gestated a foetus of his own. Er, what it? He's a man. He can't have a uterus. Or pretty much any of the complicated plumbing necessary to get sperm to ovum and then ovum from ovary to uterus. So I don't know the detail of what's in the paper but the abstract sounds as if it was written by a nutcase.
Once again, though, there was no doubt about this person's sex. He was a man. He had impregnated a woman. Every one knew he was a man.
Sex is not binary. There are exceptions to every factor you might use.
Yes, it is. Every human being, every mammal every born, is either male or female. You can say, if the body developed down the Wolffian pathway it is male and if it developed down the Müllerian pathway it is female. That works fine. Or you can say, have both functional SRY gene and functioning androgen receptors, male, lack one or the other and female. Comes to the same thing in the end.
But you know what? IT DOESN'T MATTER!
There is absolutely no way in logic you can get from "there are a tiny number of people who have medical disorders that make them rather more difficult than usual to classify as male or female" to "therefore perfectly normal males should have the right to claim to be female and make use of all the facilities set aside for females." Trans-identifying men are, to several decimal places of certainty, phenotypically and genotypically normal men. We have no difficulty in identifying this. XY chromosomes, androgen sensitivity, Wolffian reproductive tract, production of sperm and so on. That some people are trying to claim that the existence of rare chromosomal anomalies means that these people can't be unambiguously classified as male and must be allowed to claim that they're female and invade women's spaces speaks to nothing but desperation and the lack of any actual valid arguments.