The paper presents the results of literature review on McCune-Albright-Braytsev syndrome and describes the clinical case of this syndrome. McCune-Albright-Braytsev syndrome is a genetically determined disease, usually characterized by a triad of symptoms: the presence of specific cafe-au-lait spots, fibrous dysplasia of the bones and various endocrinopathies, the most frequent of which is premature sexual development. The incidence of this disease in the world varies from 1 case per 100,000 to 1 case per million in the general population. McCune-Albright-Braytsev syndrome is caused by a mutation in GNAS1 gene. This gene encodes the alpha subunit of guanosine triphosphate binding protein (G protein), which stimulates the formation of cycli...