A novel mutation Asp90Val in the SOD1 gene associated with Japanese familial ALS

We have identified a novel mutation in exon 4 of the Cu/Zn superoxide dismutase (superoxide dismutase 1: SOD1) gene (GAC to GTC), which resulted in an Asp90 to Val substitution in a Japanese family with amyotrophic lateral sclerosis (ALS) inherited as an autosomal dominant trait. The patients in this family usually died in 2–3 years without sensory or urinary impairment. The SOD1 activity was lower in the proband as compared to the normal controls. The clinical characteristics of this family resemble those of some patients heterozygous for the Asp90Ala mutation, but both the clinical features and SOD1 activity of this family differ from those of patients homozygous for the ASP90Ala mutation.