Included in the group of BFOL of the jaws are: (1) ossifying fibroma, a neoplasm, (2) fibrous dysplasia a condition associated with known mutations to the G protein subunit α (Gsα), encoded by the GNAS gene at 20q13, that couples hormone receptors to intracellular cAMP, and (3) a variety of fibro-osseous processes referred to as (cemento)-osseous dysplasias subclassified by their clinicoradiographic characteristics. The gene discussed is GNAS; the disease is fibrous dysplasia.