Dictionary of Human Evolution and Biology

  • -id > 9:3
   

Androgen Insensitivity Syndrome

An X-linked developmental anomaly in which a chromosomal XY male embryo with testicular tissue does not respond to androgens (both testosterone and DHT are present) and the individual thus appears phenotypically female. Testes are undescended, and spermatogenesis is absent. AIS is caused by microdeletions in the gene for the androgen receptor. There are two clinical classes: complete (CAIS) and partial (PAIS). CAIS individuals possess what has been described as the supermodel phenotype: affected individuals are tall, highly symmetrical and phenotypically attractive females with micromastia, have little pubic hair (hairless pseudofemale), and lack menstruation owing to a blind vagina. Aka testicular feminization (TF), androgen resistance syndrome, Lubs syndrome. AIS is the most common form of male pseudohermaphroditism. AIS is about 1.5 times more common than male pseudohermaphroditism with gynecomastia.

Full-Text Search Entries