Fig. 1
From: Fibrous dysplasia for radiologists: beyond ground glass bone matrix
Post-zygotic mutations of the α-subunit of the Gs stimulatory protein (GNAS mutations) lead to the inappropriate production of the cyclic adenosine monophosphate (cAMP). In skin, the increased concentration of cAMP results in overproduction of the enzyme tyrosinase and abnormally high melanin production, incomplete differentiation of marrow stromal cells to abnormal osteoblasts with abnormal maturation of the bony matrix, and hyperfunction of the endocrine organs