title: Two families with MYH7 distal myopathy associated with cardiomyopathy and core formations.
abstract: BACKGROUND
  Laing distal myopathy is caused by MYH7 gene mutations. Multiple families have been reported with varying patterns of skeletal and cardiac involvement as well as histopathological findings.
  
  
  METHODS
  We report 2 families with p.Glu1508del mutation with detailed electrophysiological and muscle pathology findings.
  
  
  RESULTS
  All patients displayed the classic phenotype with weakness starting in the anterior compartment of the legs with a "hanging great toe." It was followed by finger extensors involvement, relatively sparing the extensor indicis proprius, giving the appearance of a "pointing index" finger. All the affected individuals had a dilated cardiomyopathy and core formations on muscle biopsy. Unexpectedly, neurogenic changes were also observed in some individuals. Both families were initially misdiagnosed with either central core disease or hereditary neuropathy.
  
  
  CONCLUSIONS
  Recognizing the classic phenotype, screening for cardiac involvement that may be clinically silent, and determining the mode of inheritance help with selecting the appropriate genetic test.
authors.affiliation: Department of Neurology, University of Wisconsin School of Medicine and Public Health, Madison, WI.
authors.forename: Elie
authors.initials: E
authors.lastname: Naddaf
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Waclawik
mesh_terms: D000328:Adult; D001706:Biopsy; D024722:Cardiac Myosins / Q000235:genetics*; D009202:Cardiomyopathies / Q000150:complications / Q000235:genetics*; D049310:Distal Myopathies / Q000150:complications / Q000235:genetics*; D004576:Electromyography; D005192:Family Health; D005260:Female; D056726:Genetic Association Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology; D009154:Mutation / Q000235:genetics*; D018995:Myosin Heavy Chains / Q000235:genetics*; D010641:Phenotype
chemical_list: C501641:MYH7 protein, human; D024722:Cardiac Myosins; D018995:Myosin Heavy Chains