They are not saying that the X chromosome mutates to Y, but rather saying that XY doesn’t define the sex. For example, some people with XY are born with female genitalia and look female their whole lives. Sometimes they don’t find out they are XY until trying to have kids and are unable to. It isn’t like the X changes to Y over time. That isn’t possible.
I think you may have misread. The PHD isn’t saying that XY becomes XX, they are saying, genetically, a person carrying XY can be a cis woman. Biologically, XY doesn’t determine the sex.
I honestly don’t understand. What does define the sex biologically? The genitalia, then?
I always understood positions like William’s like “XY is the biologically male sex by definition, if the human develops female genitalia and feels like a woman they were biologically speaking still intended to be a man.”
I don’t understand what else there could be on an elemental level to biologically determine the sex.
There’s no one thing that defines sex, that’s what makes it so complicated. What is often thought of as “biological sex” are two clustered sets of checkboxes (e.g chromosomes, genitalia, secondary sex characteristics, primary sex hormone), but people often have a mixture from both lists. Here’s an interesting nature article on it https://web.archive.org/web/20250406095942/https://www.nature.com/articles/518288a
I was unaware that an X chromosome could mutate into a Y and vice versa over the course of a lifetime. Do we know what causes that?
They are not saying that the X chromosome mutates to Y, but rather saying that XY doesn’t define the sex. For example, some people with XY are born with female genitalia and look female their whole lives. Sometimes they don’t find out they are XY until trying to have kids and are unable to. It isn’t like the X changes to Y over time. That isn’t possible.
So not what the phd claims
I think you may have misread. The PHD isn’t saying that XY becomes XX, they are saying, genetically, a person carrying XY can be a cis woman. Biologically, XY doesn’t determine the sex.
I honestly don’t understand. What does define the sex biologically? The genitalia, then? I always understood positions like William’s like “XY is the biologically male sex by definition, if the human develops female genitalia and feels like a woman they were biologically speaking still intended to be a man.” I don’t understand what else there could be on an elemental level to biologically determine the sex.
There’s no one thing that defines sex, that’s what makes it so complicated. What is often thought of as “biological sex” are two clustered sets of checkboxes (e.g chromosomes, genitalia, secondary sex characteristics, primary sex hormone), but people often have a mixture from both lists. Here’s an interesting nature article on it https://web.archive.org/web/20250406095942/https://www.nature.com/articles/518288a