AR and partial androgen insensitivity syndrome: Androgen insensitivity syndrome consists of varying degrees of impairment in the function of the androgen receptor (AR) gene and, subsequently, androgen resistance; it can be subdivided into three phenotypes: complete androgen insensitivity syndrome (CAIS), in which the patients exhibit normal or near-normal female phenotype; partial androgen insensitivity syndrome (PAIS), in which the patients present with an ambiguous phenotype; and mild androgen insensitivity syndrome (MAIS), in which the patients have predominantly male phenotype.3