[Gamma-sarcoglycanopathy: clinico-pathological and genetic study of 11 cases].

INTRODUCTION: Limb Girdle Muscular Dystrophy type 2C (LGMD2C) is an autosomal recessive dystrophy due to the deficit of gamma-sarcoglycan, one of the proteins of the dystrophin-associated proteins complex (DAP). A new mutation in the gamma-sarcoglycan gene, 13q12, has been described recently and is exclusive of the gypsy community.

OBJECTIVE: To describe the clinicopathological and the genetic findings of eleven cases from a Spanish gypsy family with LGMD2C and the mutation C283Y.

MATERIAL AND METHODS: We describe a large gypsy family with the C283Y mutation and eleven affected patients. We have performed an extensive clinical and pathological study with immunohistochemistry and Western blot analyses in the eleven patients and a genetic study of a total of twenty-seven members of the family.

RESULTS: The patients presented a severe muscular dystrophy with a dystrophic pattern in the muscle biopsy, normal immunolabeling for dystrophin, very weak for alpha-, beta- and delta-sarcoglycan and absent for gamma-sarcoglycan. These eleven patients were found to be homozygous for the mutation and twelve other members of the family, heterozygous.

CONCLUSIONS: The clinical picture and the evolution of the disease herein described is similar to that observed in DMD. Two fundamental differences were found: the autosomal recessive mode of inheritance, and the normal immunohistochemistry and immunoblot for dystrophin in the skeletal muscle.