A Novel Mutation in Frabin (FGD4) Causing a Mild Phenotype of CMT4H in an Indian Patient

J Neuromuscul Dis. 2024;11(1):221-232. doi: 10.3233/JND-230042.

Abstract

Charcot-Marie-Tooth disease 4H(CMT4H) is an autosomal recessive demyelinating form of CMT caused by FGD4/FRABIN mutations. CMT4H is characterized by early onset and slowly progressing motor and sensory deficits in the distal extremities, along with foot deformities. We describe a patient with CMT4H who presented with rapidly progressing flaccid quadriparesis during the postpartum period, which improved significantly with steroid therapy. Magnetic resonance imaging and ultrasonography demonstrated considerable nerve thickening with increased cross-sectional area in the peripheral nerves. A nerve biopsy revealed significant demyelination and myelin outfolding. This is the first report of an Indian patient with a novel homozygous nonsense c.1672C>T (p.Arg558Ter) mutation in the FGD4 gene, expanding the mutational and phenotypic spectrum of this disease.

Keywords: Charcot-Marie-Tooth disease type 4H (CMT4H); FGD4; Indian; histopathology; novel homozygous mutation.

Publication types

  • Case Reports

MeSH terms

  • Charcot-Marie-Tooth Disease* / genetics
  • Charcot-Marie-Tooth Disease* / pathology
  • Female
  • Guanine Nucleotide Exchange Factors / genetics
  • Humans
  • Microfilament Proteins / genetics
  • Mutation
  • Pedigree
  • Phenotype

Substances

  • Microfilament Proteins
  • Guanine Nucleotide Exchange Factors
  • FGD4 protein, human

Supplementary concepts

  • Charcot-Marie-Tooth Disease, Type 4H