title: Becker muscular dystrophy with widespread muscle hypertrophy and a non-sense mutation of exon 2.
abstract: Becker muscular dystrophy features progressive proximal weakness, wasting and often focal hypertrophy. We present a patient with pain and cramps from adolescence. Widespread muscle hypertrophy, preserved muscle strength and a 10-20-fold raised CPK were noted. Muscle biopsy was dystrophic, and Western blot showed a 95% reduction of dystrophin levels. Genetic analyses revealed a non-sense mutation in exon 2 of the dystrophin gene. This mutation is predicted to result in a Duchenne phenotype, but resulted in a mild Becker muscular dystrophy with widespread muscle hypertrophy. We suggest that this unusual phenotype is caused by translation re-initiation downstream from the mutation site.
authors.affiliation: Neuromuscular Research Unit and Department of Neurology 2082, University of Copenhagen, Rigshospitalet, Blegdamsvej, DK-2100 Copenhagen, Denmark. nanna.witting@rh.regionh.dk
authors.forename: N
authors.initials: N
authors.lastname: Witting
authors.forename: M
authors.initials: M
authors.lastname: Duno
authors.forename: J
authors.initials: J
authors.lastname: Vissing
mesh_terms: D000328:Adult; D001706:Biopsy; D018389:Codon, Nonsense / Q000235:genetics*; D018450:Disease Progression; D016189:Dystrophin / Q000235:genetics*; D005091:Exons / Q000235:genetics*; D006801:Humans; D006984:Hypertrophy / Q000235:genetics / Q000473:pathology; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D009132:Muscles / Q000473:pathology* / Q000503:physiopathology; D020388:Muscular Dystrophy, Duchenne / Q000235:genetics* / Q000473:pathology* / Q000503:physiopathology; D010641:Phenotype
chemical_list: D018389:Codon, Nonsense; D016189:Dystrophin