Categories: Reproductive system phene

Links to MONDO diseases: No links.

Mendelian trait/disorder: yes

Considered a defect: yes

Key variant known: yes

Year key variant first reported: 2022

Cross-species summary: This is a type of XY difference of sexual development (XY DSD) due to variants in the sdY gene. Renamed from XY DSD (Disorder of Sexual Development), sdY-related. [24/09/2023]

Molecular basis: Bertho et al. (2022) "amplified and sequenced sdY gene between exons 2 and 3 of XY Chinook salmon females and found that they have a missense mutation in the third exon of the sdY gene that produces a single amino acid change (I183N) in a highly conserved position of the SdY protein, while males have the wild-type copy of SdY. The mutation modifies the 3-dimensional (3D) structure. The mutant SdY I183N protein is less stable than the wild-type SdY and is affected in its ability to interact with its protein partner, Foxl2 . . . . This failure in turn leads to the inability to repress the cyp19a1a promoter and thereby to suppress female development. Altogether our results suggest that the sdY-N183 copy in XY Chinook salmon females is inactive and cannot block the female pathway in the same way as the wild-type sdY gene. Our results provide an explanation for the existence of naturally occurring XY Chinook salmon females and support the role of sdY as the master male sex-determining gene of Chinook salmon."

Genetic engineering: Unknown
Have human generated variants been created, e.g. through genetic engineering and gene editing

Prevalence: Bertho et al. (2022): "The incidence of these XY females varies between 20% and 38% in Central Valley rivers while ranging between 0% and 14% under hatchery conditions . . . . In addition, independent surveys found proportions of wild-caught XY females ranging from 12% . . . up to 84%".

Associated gene: