Striking phenotypic variability in two familial cases of myosin storage myopathy with a MYH7 Leu1793pro mutation

Neuromuscul Disord. 2009 Feb;19(2):163-6. doi: 10.1016/j.nmd.2008.11.012. Epub 2009 Jan 12.

Abstract

Myosin Storage Myopathies (MSM) have emerged as a new group of inherited myopathies with heterogenous clinical severity and age of onset. We have identified in a woman and her daughter, a pLeu1793Pro mutation in MYH7. This mutation has already been reported to be associated with MSM presenting as neonatal hypotony. Our index case complained of proximal muscle weakness at age 30. Her daughter presented at birth with a cardiomyopathy without any skeletal muscle involvement. This report underlines the clinical variability of MSM even with a given mutation or in a same family.

Publication types

  • Case Reports

MeSH terms

  • Amino Acid Substitution / genetics
  • Cardiac Myosins / genetics*
  • Cardiomyopathies / congenital
  • Cardiomyopathies / genetics
  • Cardiomyopathies / physiopathology
  • DNA Mutational Analysis
  • Female
  • Genetic Predisposition to Disease / genetics*
  • Genetic Variation / genetics
  • Genotype
  • Heart / physiopathology
  • Humans
  • Leucine / genetics
  • Middle Aged
  • Muscle Hypotonia / congenital
  • Muscle Hypotonia / genetics
  • Muscle Hypotonia / physiopathology
  • Muscle, Skeletal / metabolism
  • Muscle, Skeletal / pathology
  • Muscle, Skeletal / physiopathology*
  • Muscular Diseases / genetics*
  • Muscular Diseases / metabolism
  • Muscular Diseases / physiopathology*
  • Mutation / genetics*
  • Myocardium / metabolism
  • Myocardium / pathology
  • Myosin Heavy Chains / genetics*
  • Phenotype
  • Proline / genetics
  • Young Adult

Substances

  • MYH7 protein, human
  • Proline
  • Cardiac Myosins
  • Myosin Heavy Chains
  • Leucine