Mutations in the small GTP-ase late endosomal protein RAB7 cause Charcot-Marie-Tooth type 2B neuropathy

Am J Hum Genet. 2003 Mar;72(3):722-7. doi: 10.1086/367847. Epub 2003 Jan 21.


Charcot-Marie-Tooth type 2B (CMT2B) is clinically characterized by marked distal muscle weakness and wasting and a high frequency of foot ulcers, infections, and amputations of the toes because of recurrent infections. CMT2B maps to chromosome 3q13-q22. We refined the CMT2B locus to a 2.5-cM region and report two missense mutations (Leu129Phe and Val162Met) in the small GTP-ase late endosomal protein RAB7 which causes the CMT2B phenotype in three extended families and in three patients with a positive family history. The alignment of RAB7 orthologs shows that both missense mutations target highly conserved amino acid residues. RAB7 is ubiquitously expressed, and we found expression in sensory and motor neurons.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Charcot-Marie-Tooth Disease / classification
  • Charcot-Marie-Tooth Disease / genetics*
  • Chromosome Mapping
  • Chromosomes, Human, Pair 3*
  • Cloning, Molecular
  • Female
  • Humans
  • Male
  • Molecular Sequence Data
  • Mutation*
  • Pedigree
  • Recombinant Proteins / chemistry
  • Recombination, Genetic
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • rab GTP-Binding Proteins / chemistry
  • rab GTP-Binding Proteins / genetics*
  • rab7 GTP-Binding Proteins


  • Recombinant Proteins
  • rab7 GTP-Binding Proteins
  • rab7 GTP-binding proteins, human
  • rab GTP-Binding Proteins

Associated data

  • GENBANK/O04157
  • GENBANK/P09527
  • GENBANK/P32939
  • GENBANK/P36411
  • GENBANK/P51149
  • GENBANK/P51150
  • OMIM/162400
  • OMIM/600882