Myopathies caused by homozygous titin mutations: limb-girdle muscular dystrophy 2J and variations of phenotype

J Neurol Neurosurg Psychiatry. 2010 Nov;81(11):1200-2. doi: 10.1136/jnnp.2009.178434. Epub 2010 Jun 22.

Abstract

Limb-girdle muscular dystrophy 2J caused by mutations in C-terminal titin has so far been identified in Finnish patients only. This may in part be due to limited availability of diagnostic tests for titin defects. In this report, a French family with an autosomal-dominant late-onset distal myopathy of the tibial muscular dystrophy phenotype segregating in several members of the family was described. One deceased patient in the family proved to be homozygous for the C-terminal truncating titin mutation because of consanguinity. According to available medical records, the patient had a clearly more severe generalised muscle weakness and atrophy phenotype not recognised as a distal myopathy at the time. Autopsy findings in one of the original Finnish limb-girdle muscular dystrophy 2J patients were reported and the early phenotype in a newly identified young patient with homozygous Finnish C-terminal titin mutation (FINmaj) was detailed.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged, 80 and over
  • Child
  • Connectin
  • Fatal Outcome
  • Female
  • Finland
  • France
  • Homozygote
  • Humans
  • Male
  • Middle Aged
  • Muscle Proteins / chemistry
  • Muscle Proteins / genetics*
  • Muscular Dystrophies, Limb-Girdle / genetics*
  • Muscular Dystrophies, Limb-Girdle / physiopathology*
  • Pedigree
  • Phenotype
  • Point Mutation*
  • Protein Kinases / chemistry
  • Protein Kinases / genetics*
  • Protein Structure, Tertiary

Substances

  • Connectin
  • Muscle Proteins
  • TTN protein, human
  • Protein Kinases