Prepubertal daughters of women with PCOS exhibit increased whole body 5alpha-reductase activity [36], enhancing target organ exposure to androgen action before menarche, while pre- and peripubertal daughters exhibit hyperandrogenism [18,33,124], including elevated ‘free’ T (not bound to sex hormone binding globulin, SHBG) [33], along with consistently elevated ovarian AMH levels from infancy [18,31,32] and LH hypergonadotropism during adolescence [18]. The gene discussed is PLOD1; the disease is polycystic ovary syndrome.