Résumé
McCune-Albright syndrome (MAS) is a sporadic disease classically including polyostotic fibrous dysplasia, cafe -au-lait spots, sexual precocity, and other hyperfunctional endocrinopathies. Recent investigations suggest an etiological role for activating embryonic somatic missense mutations in the gene for the a subunit of Gs (Gsa), the G protein that stimulates adenylyl cyclase. DNA from bone, ovary, and blood was analyzed by using polymerase chain reaction and sequenced. A embryological somatic mutation of Gsa gene encoding substitution of a Cys for Arg at amino acid 201 from cells of dysplastic bone and ovary was observed, and the distribution of mutant gene reveals mosaic pattern. We report a case of McCune-Albright syndrome with an activating mutation at codon 201 of Gsa subunit on ovary and bone tissue that was experienced recently.