This review is specifically concerned with non-CAH 46,XX DSD, including other disorders of androgen excess such as aromatase deficiency with CYP19A1 mutation, disorders of gonadal development (ovotesticular DSD, 46XX men or 46,XX testicular DSD, and monogenic forms of primary ovarian insufficiency with mutations in genes involved in ovarian development), and unclassified disorders with MRKH syndrome (Table 2). The gene discussed is CYP19A1; the disease is hyperandrogenism.