45,X/46,XY mosaicism

45,X/46,XY mosaicism
Other names45,X0/46,XY MGD
SpecialtyObstetrics and gynaecology, endocrinology, medical genetics Edit this on Wikidata

45,X/46,XY mosaicism, also known as X0/XY mosaicism and mixed gonadal dysgenesis,[1] is a mutation of sex development in humans associated with sex chromosome aneuploidy and mosaicism of the Y chromosome. It is a fairly rare chromosomal disorder at birth, with an estimated incidence rate of about 1 in 15,000 live births.[2] Mosaic loss of the Y chromosome in previously non-mosaic men grows increasingly common with age.[3]

The clinical manifestations are highly variable, ranging from partial virilisation and ambiguous genitalia at birth, to patients with completely male or female gonads. Most individuals with this karyotype have apparently normal male genitalia, and a minority have female genitalia, with a significant number of individuals showing genital abnormalities or mixed sex characteristics.[4] A significantly higher than average number of other developmental abnormalities are also found in individuals with X0/XY mosaicism.[4] Psychomotor development is normal.

  1. ^ "45,X/46,XY including Y chromosome rearrangements" (PDF). rarechromo.org. Retrieved 15 July 2024.
  2. ^ Johansen, Marie Lindhart; et al. (1 August 2012). "45,X/46,XY Mosaicism: Phenotypic Characteristics, Growth, and Reproductive Function—A Retrospective Longitudinal Study". The Journal of Clinical Endocrinology & Metabolism. 97 (8): E1540–E1549. doi:10.1210/jc.2012-1388. PMID 22605431.
  3. ^ Zhou W, Machiela MJ, Freedman ND, Rothman N, Malats N, Dagnall C, et al. (2016). "Mosaic loss of chromosome Y is associated with common variation near TCL1A". Nat Genet. 48 (5): 563–8. doi:10.1038/ng.3545. PMC 4848121. PMID 27064253.
  4. ^ a b Chang, H. J.; Clark, R. D.; Bachman, H. (1990). "The phenotype of 45,X/46,XY mosaicism: An analysis of 92 prenatally diagnosed cases". American Journal of Human Genetics. 46 (1): 156–167. PMC 1683543. PMID 2294747.