A rare case of McCune Albright syndrome

Abstract

McCune Albright syndrome (MAS) is a rare genetic disorder that occurs due to the mutation in the guaninenucleotide binding protein alpha-subunit (GNAS1) gene. Its prevalence is estimated to range between 1/100 000 and 1/1 000 000. This mutation of GNAS gene is a post-zygotic event, which leads to a mosaic presentation of the gene. This explains the broad clinical spectrum of this disease. It is characterized by the clinical triad of peripheral precocious puberty, polyostotic fibrous dysplasia, and café-au-lait skin pigmentation. Many other endocrinopathies are associated with MAS, including hyperthyroidism, growth hormone excess, phosphate wasting and neonatal hypercortisolism.