Charcot-Marie-Tooth type X: unusual phenotype of a novel CX32 mutation

Eur J Neurol. 2008 Oct;15(10):1140-2. doi: 10.1111/j.1468-1331.2008.02263.x. Epub 2008 Aug 20.

Abstract

Background: X-linked Charcot-Marie-Tooth disease (CMTX), caused by mutations in the gene encoding connexin32, is the second most common form of inherited demyelinating neuropathy, next to CMT 1A, and accounts for 10-20% of all hereditary demyelinating neuropathies.

Aims of the study: To describe clinical and electrophysiological data of an Italian family carrying a novel mutation in the Cx32 gene.

Patients and methods: Clinical, electrophysiological, and genetic findings of three patients carrying the Ser128Leu mutation in the intracellular domain of the Cx32 gene were reported. Brain MRI studies were also performed.

Results: In our family the disease was characterized by a moderate-to-severe polyneuropathy affecting similarly males as well females. In the proband the phenotype was quite unusual in terms of late-onset, rapidity of evolution and severity. Abnormal brain MRI in association with CNS symptoms were also observed. Both sons had also clinical evidence of CNS involvement.

Conclusions: The Ser128Leu mutation in the Cx-32 gene is a novel substitution, which has not been reported so far. This novel mutation could be added to the group of Cx-32 mutations with CNS phenotypes. The identification of new CMTX causing mutations is a crucial step for carrier detection and pre-symptomatic diagnosis.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Age of Onset
  • Amino Acid Substitution
  • Brain / pathology
  • Charcot-Marie-Tooth Disease / epidemiology
  • Charcot-Marie-Tooth Disease / genetics*
  • Connexins / genetics*
  • Female
  • Gap Junction beta-1 Protein
  • Humans
  • Italy / epidemiology
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Mutation, Missense*
  • Phenotype
  • Point Mutation*

Substances

  • Connexins