Polyostotic Fibrous Dysplasia MedTerms

Description: Definition of Polyostotic fibrous dysplasia Polyostotic fibrous dysplasia: A genetic disorder of bones, skin pigmentation and hormonal problems with premature sexual development. Also called McCune-Albright syndrome or the Albright syndrome. In the syndrome, there is bone disease with fractures and deformity of the legs, arms and skull; pigment patches of the skin; and endocrine (hormonal) disease with early puberty (early menstrual bleeding, development of breasts and pubic hair) and an increased rate of growth. Polyostotic fibrous dysplasia is usually caused by mosaicism for a mutation in a gene called GNAS1 (Guanine Nucleotide binding protein, Alpha Stimulating activity polypeptide 1).