[Analysis of a pedigree with distal hereditary motor neuropathy type 2A caused by mutation in HSPB8 gene]

To explore phenotypic and mutational characteristics of a pedigree with distal hereditary motor neuropathy (dHMN).

Clinical data of the proband and her family members was collected. Electrophysiology, muscle biopsy and whole exome sequencing were carried out for the proband.

Patients of the family mainly presented with distal lower limb weakness. Electrophysiological test of the proband revealed distal motor neuropathy and sensory nerves were normal. Muscle biopsy suggested neurogenic atrophy of muscle fibers. Genetic analysis revealed a heterozygous c.421A>G (p.K141E) mutation in exon 2 of the HSPB8 gene, which was a hot spot mutation.

This family was the first reported HSPB8 related dHMN2A in Chinese population, and p.K141E was the causative mutation, which enriched the mutational spectrum of dHMN in China.