We report a novel missense mutation (G37V) in exon 2 of the superoxide dismutase-1 gene in a 63-years-old Japanese male with purely lower motor neuron disease.
The alanine to valine mutation at codon 4 (A4V) of SOD1 causes a rapidly progressive dominant form of amyotrophic lateral sclerosis (ALS) with exclusively lower motor neuron disease and is responsible for 50% of SOD1 mutations associated with familial ALS in North America.This mutation is rare in Europe.