McCune-Albright syndrome (MAS) is classically manifested as a triad of irregular cafe au lait spots, fibrous dysplasia of long bones with cysts, and precocious pubey (sexual precocity). This is a sporadic disorder caused by somatic (postzygotic) activating mutations in the GSalpha subunit that links G protein-coupled receptors to intracellular signaling pathways. Precocious pubey may be central or incomplete. Other clinical manifestations include, Hypehyroidism Adrenal nodules with Cushing syndrome Acromegaly Hyperprolactinemia Hyperparathyroidism Hypophosphatemic hyperphosphaturic rickets Autonomous endogenous-functioning ovarian cysts (in girls) Must know: Causes of Precocious Pubeal Development: Central (GnRH-dependent) precocious pubey: Idiopathic Central nervous system abnormalities Acquired--abscess, chemotherapy, radiation, surgical trauma Congenital--arachnoid cyst, hydrocephalus, hypothalamic hamaoma, septo-optic dysplasia, suprasellar cyst Tumors--astrocytoma, craniopharyngioma, glioma Peripheral (GnRH-independent) precocious pubey: Congenital adrenal hyperplasia Adrenal tumors McCune-Albright syndrome Familial male-limited gonadotropin independent precocious pubey Gonadal tumors Exogenous estrogen--oral (contraceptive pills) or topical Ovarian cysts (females) HCG-secreting tumors (eg, hepatoblastomas, choriocarcinomas) (males) Ref: Styne D. (2011). Chapter 15. Pubey. In D.G. Gardner, D. Shoback (Eds), Greenspan's Basic & Clinical Endocrinology, 9e.