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Published on: September 29, 2014
Phenotypic variability in siblings with calpainopathy (LGMD2A)
J Schessl1, M C Walter, G Schreiber
1Division of Neurology, The Children's Hospital of Philadelphia, and University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
Abstract:
Calpainopathy is an autosomal-recessive limb girdle muscular dystrophy (LGMD2A) characterized by selective atrophy and weakness of proximal limb girdle muscles. The clinical phenotype of the disease is highly variable inter-familial, but little is known about intra-familial variability. This study reports the phenotypic variability in eight sibling pairs with genetically proven LGMD2A. Although siblings with identical mutations were often similarly affected, in some families the age of onset and the clinical course varied considerably.
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