Novel mutations in HINT1 gene cause the autosomal recessive axonal neuropathy with neuromyotonia.

Abstract

Autosomal recessive axonal neuropathy with neuromyotonia (ARAN-NM) is a rare form of hereditary neuropathy. Mutations in HINT1 gene have been identified to be the cause of this disorder. We report two unrelated patients who presented gait impairment, progressive distal muscle weakness and atrophy, neuromyotonia and foot deformities. Electrophysiological studies showed axonal motor neuropathy and neuromyotonic discharges. Using Next-generation sequencing, we identified two homozygous mutations, NM_005340.6: c.112T\u202f>\u202fC; p.(Cys38Arg) and NM_005340.6: c.289G\u202f>\u202fA; p.(Val97Met) in HINT1 gene. Based on the clinical presentation and molecular genetic analyses, ARAN-NM was diagnosed in both patients and NM_005340.6: c.112T\u202f>\u202fC; p.(Cys38Arg) and NM_005340.6: c.289G\u202f>\u202fA; p.(Val97Met) in HINT1 gene were believe to be causative for the disorder.