Androgen insensitivity syndrome (AIS) is typically characterized by evidence of feminization of the external genitalia at birth, abnormal secondary sexual development in puberty, and infertility in individuals with a 46,XY karyotype. AIS represents a spectrum of defects in androgen action. Pathogenesis is the result of mutations in the X-linked androgen receptor (AR) gene, which encodes for the ligand-activated androgen receptor.