Oh, that is not quite the case. There are many cases of men having XX chromosomes, and women with XY chromosomes.While I understand the distinction such is not acceptable from a medical professional. I personally do not want my doctor catering to the gender identity language and associated agendas. We all know we are genetically set at conception as XX or XY, Female or male. Females are called women or girls or lady or miss and so on. Males are called boys, men, Mr. gentlemen and such.
During their early development, our embryos follow a female-ish template by default. Male-associated features require a protein (SRY) to go into the nucleus and "awaken" a set of regulatory genes, which will then go about the business of converting the embryo into a male (SRY and similar proteins are called transcription factors and are extremely important for hereditary diseases, since they control all other genes). SRY is normally encoded in the Y-chromosome, so under ordinary circumstances if you have a Y you're a man, and if you don't you're a woman.
But there are billions of people, and embryonic development is a messy process. Mistakes happen. What if, say, your SRY mutates so that it no longer functions? Well, then you follow the default female path of development, and end up a woman with XY chromosomes (and some developmental defects, as two X chromosomes are in fact needed for some parts of gonadal development). What happens if SRY gets "lost" and transferred to the X chromosome, which is partially identical to Y and recombines with it during meiosis? Well, the embryo in question becomes a man, despite having XX chromosomes.
These cases are usually infertile, but very rarely they can have children - see here, for example. Should we say in these cases that a woman has sired a child, or a man has bore one? Similarly, a related disease involves a defect in the receptor that senses and responds to testosterone, so even though the person is XY and SRY is functional, you end up with an externally (and in rare cases functionally) female individual. If such a person gives birth, can the child go on to kill Macbeth?
However, I generally agree that "can a man give birth?" is a question along the lines of "is a rat bigger than a dog?". Yes, there are cloud-rats in the rainforest and pouched rats in the savanna that grow to be larger than many breeds, but if your child asks such a question you should not be blamed for answering "no".
In addition, the issue of transgender people in sports is a different matter. Leaving aside existential questions about what is and isn't a woman, the influence of pre-transition hormonal development is massive. It's as if you've taken a baby and gave her doping for twenty years before letting her loose into the competition. If we don't allow Russia to produce doped-up babies for the Olympics, we shouldn't allow transgender women either.
(Transgender men, in contrast, should probably be allowed to compete in men's sports as they don't have an unfair advantage).
Last edited: