Diagnosis is recommended based on the International PCOS Guideline criteria, with diagnosis confirmed in adults when 2 of out the following 3 criteria are met: (i) hyperandrogenism (clinical or biochemical); (ii) irregular cycles; and (iii) polycystic ovary morphology or elevated anti-Müllerian hormone (AMH) levels. The gene discussed is AMH; the disease is polycystic ovary syndrome.