>>12894848Medi fag with BA in physiology and developmental biology here.
XYY is a thing, so their sons can be extra masculine.
However males and females turn on or off different genes, and when you inherit the DNA from your parents getting two copies of your chromosomes with different gender specific methylation or epigenetic imprinting is vital for producing a healthy child.
Sometimes people get an extra chromosome from a parent, this is called trisomy and causes things like the downs. Similarly sometimes a zygote is missing a chromosome from a parent, these almost always result in miscarriage's (assuming it developed to the point where the mother even knows she was pregnant). When you get two copies of a chromosome from one parent and no copies of the same chromosome from the other parent you have what's called uniparental disomy, while there is some small chance of doubling up a recessive disorder most issues that arise from this are caused by not having a copy of a chromosome with both male and female methylation.
Two well known disorders caused by this are Prader–Willi syndrome and Angelman syndrome, each can be caused by a single chromosome having uni-gendered metalation on chromosome 15. Uni-gendered metalation on chromosome 14 is also known to cause particular symptoms such as skeletal abnormalities, intellectual disability, and joint contractures, among others.
Getting a zygote to start growing is one thing but bringing it to term and seeing how it's fucked up is a totally different thing. I can only imagine the unwholly abomination that would result from having uni-gendered metalation on all chromosomes, assuming such a thing would even be viable. I'm not saying it's insurmountable, perhaps they can figure out how to manipulate the epigenome to a degree where these issues can be solved but it won't be easy or simple.
