A novel MPZ mutation in Charcot-Marie-Tooth disease type 1B with focally folded myelin and multiple entrapment neuropathies

Neuromuscul Disord. 2012 Feb;22(2):166-9. doi: 10.1016/j.nmd.2011.08.005. Epub 2011 Sep 21.


Charcot-Marie-Tooth type 1B (CMT1B) is a demyelinating neuropathy caused by mutations in the myelin protein zero (MPZ) gene. Here, we describe a patient with CMT1B with focally folded myelin, a rarely reported phenotype of CMT1B, who initially presented with multiple entrapment neuropathies. She complained of palmar dysesthesia on both sides and on both soles of her feet in her 30's. She underwent bilateral carpal and tarsal tunnel release at age 44, which provided transient relief from the symptoms. A sural nerve biopsy performed at age 49 revealed focally folded myelin. Molecular genetic analysis revealed a novel Asn131Ser mutation in MPZ.

Publication types

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

MeSH terms

  • Charcot-Marie-Tooth Disease / diagnosis*
  • Charcot-Marie-Tooth Disease / genetics*
  • Charcot-Marie-Tooth Disease / pathology
  • DNA Mutational Analysis
  • Demyelinating Diseases / genetics
  • Demyelinating Diseases / pathology
  • Female
  • Humans
  • Middle Aged
  • Mutation / genetics
  • Myelin P0 Protein / genetics*
  • Myelin Sheath / genetics
  • Myelin Sheath / pathology*
  • Myelin Sheath / ultrastructure
  • Nerve Compression Syndromes / genetics*
  • Nerve Compression Syndromes / pathology
  • Phenotype
  • Sural Nerve / pathology
  • Sural Nerve / ultrastructure


  • Myelin P0 Protein