International Skeptics Forum - View Single Post - Differences in Sex Development (aka "intersex")

Louden Wilde · 26th November 2021, 12:38 PM

Originally Posted by d4m10n

Can you be more specific as to referent of the highlighted word?

Seems to me that the gamete binary accounts for > 99% of live births, that is, people who are born with oocytes or on a developmental pathway to produce sperm. The remaining fraction of a percent are the subject of this thread, and a fascinating subject in and of itself, quite apart from "judgements humans as a society have made on how each sex looks and behaves." I was surprised to learn (for example) that individuals with de la Chapelle syndrome^WP may be fully masculinized due to the presence of an anomalous SRY gene, despite being genetically 46,XX.

But note folks with this syndrome are sterile (so it's still definitely a DSD) - likely due to incompatibilities between X chromosome inactivation in mammals and being a functional male. There are rodents (notably genus Tokudaia - "spiny rats") that lack a Y Chom and mostly SRY, but they are X/0. Note the main function of the SRY protein is to trigger expression of a related gene/protein, Sox9 that subsequently starts the male developmental cascade - these rodents have a Sox9 gene, but it does not respond to SRY protein

26th November 2021, 12:38 PM	#11
Louden Wilde Critical Thinker Join Date: Oct 2020 Location: NYC Posts: 380	Originally Posted by d4m10n Can you be more specific as to referent of the highlighted word? Seems to me that the gamete binary accounts for > 99% of live births, that is, people who are born with oocytes or on a developmental pathway to produce sperm. The remaining fraction of a percent are the subject of this thread, and a fascinating subject in and of itself, quite apart from "judgements humans as a society have made on how each sex looks and behaves." I was surprised to learn (for example) that individuals with de la Chapelle syndrome^WP may be fully masculinized due to the presence of an anomalous SRY gene, despite being genetically 46,XX. But note folks with this syndrome are sterile (so it's still definitely a DSD) - likely due to incompatibilities between X chromosome inactivation in mammals and being a functional male. There are rodents (notably genus Tokudaia - "spiny rats") that lack a Y Chom and mostly SRY, but they are X/0. Note the main function of the SRY protein is to trigger expression of a related gene/protein, Sox9 that subsequently starts the male developmental cascade - these rodents have a Sox9 gene, but it does not respond to SRY protein