McCune–Albright syndrome (MAS) is a non-hereditary genetic disorder this is caused by a spontaneous postzygotic mutation of the gene GNAS, which is involved in G-protein signalling and results in constitutive activation of Gsα protein as well as the production of excess cAMP160,161 The GNAS mutation arises very early during embryogenesis and occurs only in the mosaic state, which leads to a variable pattern in affected tissues.162. This evidence concerns the gene GNAS and hereditary disease.