AR, also named as DHTR and NR3C4, belongs to the nuclear hormone receptor family and NR3 subfamily. AR is a ligand-activated transcription factors that regulate eukaryotic gene expression and affect cellular proliferation and differentiation in target tissues. Transcription factor activity is modulated by bound coactivator and corepressor proteins. AR is activated, but not phosphorylated, by HIPK3. Defects in AR are the cause of androgen insensitivity syndrome (AIS), previously known as testicular feminization syndrome (TFM), which is an X-linked recessive form of pseudohermaphroditism due end-organ resistance to androgen. Defects in AR are the cause of spinal and bulbar muscular atrophy X-linked type 1 (SMAX1) which also known as Kennedy disease. Defects in AR may play a role in metastatic prostate cancer. Defects in AR are the cause of androgen insensitivity syndrome partial (PAIS) which also known as Reifenstein syndrome.