<prompt> Gs-alpha mutation may lead to? -Mc cune Albright syndromePseudohypoparathyroidismPseudopseudohypoparathyroidismAll of the above  <response>: Gs alpha mutations in fibrous dysplasia and McCune-Albright syndrome. Weinstein LS1. Author information Abstract Fibrous dysplasia FD is a focal bone lesion composed of immature mesenchymal osteoblastic precursor cells. Some FD patients also have hyperpigmented skin lesions cafe-au-lait spots, gonadotropin-independent sexual precocity, andor other endocrine and nonendocrine manifestations McCune-Albright syndrome . MAS results from somatic mutations occurring during early development, resulting in a widespread mosaic of normal and mutant-bearing cells, which predicts that the clinical presentation of each patient is determined by the extent and distribution of abnormal cells. These mutations encode constitutively active forms of Gsalpha, the ubiquitously expressed G protein alpha-subunit that couples hormone receptors to intracellular cAMP generation. These mutations lead to substitution of amino acid residues that are critical for the intrinsic GTPase activity that is normally required to deactivate the G protein. It also may lead to pseudo and psuedopseudohypoparathyroidism. 