Phenotypic features and genetic findings in 2 chinese families with Miyoshi distal myopathy

Arch Neurol. 2004 Oct;61(10):1594-9. doi: 10.1001/archneur.61.10.1594.

Abstract

Background: Miyoshi distal myopathy (MM) and limb girdle muscular dystrophy type 2B (LGMD2B) were found to map to the same mutant gene encoding for dysferlin on chromosome 2p13. Most reported cases were large inbred kindreds whose members demonstrated both MM and LGMD2B phenotypes.

Objective: To investigate the clinical, neurophysiological, histopathological, and genetic features in 4 patients with MM from 2 unrelated Chinese families demonstrating linkage to the dysferlin locus.

Results: All patients were characterized by early adult onset, preferential atrophy, and weakness of calf muscles, marked elevation of serum creatine kinase levels, and absence of dysferlin staining. Magnetic resonance imaging showed fatty and fibrotic tissue signals in the affected muscles. Genetic analysis revealed novel compound heterozygous mutations, 1310+1G to A and GGG to GTC transition at nucleotide 1650 (G426V ) in one family and another novel compound heterozygous mutation, a deletion of C at nucleotide 477 and a CCG to CTG transition at nucleotide 6576 (P2068L), in the other family.

Conclusion: Miyoshi distal myopathy in these 2 Chinese families demonstrated a homogenous phenotype and compound heterozygous mutations. Among the 4 mutations, 3 were novel mutations that, to our knowledge, have not been reported previously.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Asian People
  • DNA Mutational Analysis / methods
  • Distal Myopathies / genetics*
  • Distal Myopathies / pathology
  • Dysferlin
  • Exons
  • Family Health*
  • Female
  • Genetic Linkage
  • Genotype
  • Glycine / genetics
  • Humans
  • Immunohistochemistry / methods
  • Leucine / genetics
  • Magnetic Resonance Imaging / methods
  • Male
  • Membrane Proteins / genetics*
  • Muscle Proteins / genetics*
  • Muscle Proteins / metabolism
  • Muscle, Skeletal / pathology
  • Muscular Diseases / genetics
  • Muscular Diseases / pathology
  • Mutation / genetics
  • Pedigree
  • Phenotype*
  • Polymorphism, Single-Stranded Conformational
  • Proline / genetics
  • Valine / genetics

Substances

  • DYSF protein, human
  • Dysferlin
  • Membrane Proteins
  • Muscle Proteins
  • Proline
  • Leucine
  • Valine
  • Glycine