After watching the most recent Serial Brain video re: Sally Yates is a man, it brings into focus a theory I've been working on for a while.
Y = transgender or genetically altered
The Y chromosome is the male chromosome.
Genetic Engineering: Is it possible to clone an opposite-gender version of yourself?
Yes, but only for a female version of the male, not the other way around.
To change a male to a female, simply remove the Y chromosome and duplicate the existing X chromosome.
There's no real way to change a female to a male because there is no Y chromosome to duplicate.
https://www.quora.com/Genetic-Engineering-Is-it-possible-to-clone-an-opposite-gender-version-of-yourself