Characterization of mutations in fifty North American patients with X-linked myotubular myopathy

Hum Mutat. 2002 Feb;19(2):114-21. doi: 10.1002/humu.10033.


X-linked myotubular myopathy (MTM1) is a rare developmental disorder of skeletal muscle that is characterized by the presence of abnormal central nuclei in biopsy specimens taken from affected individuals. To date 133 different mutations have been identified in the MTM1 gene worldwide. We report here mutations detected in 50 additional U.S. families with biopsy-proven MTM1. Forty-one of the patients have not been described previously, including 18 with novel mutations. Eighty-eight percent of the mothers of sporadic cases that were studied were identified as carriers, extending the previously reported high-carrier frequency for this disorder. Clinical information collected on the majority of patients helps to further correlate genotype with phenotype, and implications of these data for genetic counseling in families are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Child
  • Child, Preschool
  • DNA Mutational Analysis
  • Exons / genetics
  • Female
  • Genetic Counseling
  • Genetic Linkage / genetics*
  • Heterozygote
  • Humans
  • Infant
  • Introns / genetics
  • Male
  • Molecular Sequence Data
  • Mutation / genetics*
  • Myopathies, Structural, Congenital / congenital
  • Myopathies, Structural, Congenital / genetics*
  • Myopathies, Structural, Congenital / physiopathology*
  • Phenotype
  • Polymorphism, Genetic / genetics
  • Protein Tyrosine Phosphatases / genetics*
  • Protein Tyrosine Phosphatases, Non-Receptor
  • Reverse Transcriptase Polymerase Chain Reaction
  • United States
  • X Chromosome / genetics*


  • Protein Tyrosine Phosphatases
  • Protein Tyrosine Phosphatases, Non-Receptor
  • myotubularin

Associated data

  • GDB/119439
  • GENBANK/AF002223
  • GENBANK/U46024
  • OMIM/310400