Definition

Androgen insensitivity syndrome is a genetic condition where affected people have male chromosomes and male gonads (testicles). The external genitals, however, have mild to complete feminization.

Description

Normal sexual development

In normal development, the chromosome sex determines the gonadal sex, which in turns determines the phenotypic sex. The chromosome sex is determined at conception; a male has the sex chromosome pair XY and a female has the chromosome pair XX. During the first 40 days of gestation, a male and female embryo appear the same and have undifferentiated gonads, which have the potential of becoming testes or ovaries. The presence of the Y chromosome in the male directs the...