POMT2 gene mutation in limb-girdle muscular dystrophy with inflammatory changes.

Defects in glycosylation of alpha-dystroglycan are associated with several forms of muscular dystrophies. Mutations in POMT2 gene have been identified in patients with congenital muscular dystrophy and brain involvement, either characterized by a Walker-Warburg/muscle-eye-brain phenotype, or by microcephaly, mental retardation, and cerebellar hypoplasia. We identified a POMT2 homozygous missense mutation in a girl with a mild limb-girdle muscular dystrophy (LGMD) phenotype, marked elevated serum creatine kinase levels, and absence of brain involvement. Muscle biopsy revealed myopathic and inflammatory changes and severe alpha-dystroglycan reduction. In view of the remarkable mild clinical picture, we propose to designate this phenotype as LGMD2N.