3w ago

genotype rarity: ⭐⭐⭐⭐⭐

"A Novel Sex Chromosome Mosaicism 45,X/45,Y/46,XY/46,YY/47,XYY Causing Ambiguous Genitalia"

21 comments

Ambiguous Genitalia would make a good pub quiz team name.
- The Novel Sex Chromosomes was the name of my college marching band
  
  45,X/46,XX, 45,X/46,XY and 46,XY/47,XXY was my locker combination in high school!

nobody called me on this actually being karyotypes and not genotypes. I'm disappointed

Is YY possible though? Never heard of that one.
- I think it's not, since the X chromosome contains vital genes while the Y chromosome kinda does nothing. If you don't have an X chromosome, you should be missing important genes. I might be wrong though.
  
  I heard about XYY, XXY and even XXX so was wondering about this one. Since it's still 50/50 (more or less) and it has to contain at least one X, I would guess. Still confused by the article title though.
- You can be XYY and doctors will shorten that informally to YY. https://www.webmd.com/a-to-z-guides/what-are-yy-chromosomes
  
  I see. That makes sense.
- Normally no, since one gonosome comes from each parent: The mother (XX) and the father (XY).
  If somehow a series of unfortunate meioses occurred to create a zygote that had two Y chromosomes and no X chromosome, the foetus would absolutely not be viable, since the X chromosome contains many essential genes, while the Y chromosome is a truncated version that has less than half the information
  
  There are situations that occur during fertilization, if the egg somehow loses it genetic material, the sperm enters the egg, but it duplicates its own half genome to form a 46 pairs but this is abnormal, because the gene pattering and also epigenetic silencing is different from males and females, so it forms abnormal mass of tissue called a mole; it can be partial or complete, one of the types can become a rare form of cancer
- If YY happens, the fetus will not form normally and you will probably have at best a miscarriage

Interesting how they call this child a "boy" if the karyotype and genitalia are so ambiguous. Like, why???
- A three years old apparently male child was referred to Anhui Provincial hospital with a complaint of undifferentiated external genitalia.
  It might just be that that's what they're registered as, or how parents referred to them, I guess?
  
  Well, the child is three years old and certainly has no concept of gender/sex. So how and why is someone apparently assigning gender and sex to this child? Why not just keep it neutral? Especially in context of forced gender and sex assignations as well as intersex child mutilations. Shouldn't we be much more careful in this context not to force our biases and weird ideas of gender/sex onto children?!

21 comments