Confirmation of the severe phenotypic effect of serine at codon 41 of the superoxide dismutase 1 gene

INTRODUCTION: A Gly41Ser mutation in the superoxide dismutase 1 gene (SOD1) has been reported to cause a very rapid course of amyotrophic lateral sclerosis (ALS) in a limited number of Italian patients, but a Gly41Asp mutation results in a more benign course. METHODS: Four members of an African American family with autosomal dominant ALS were evaluated clinically over 12 years. Mutation analysis of SOD1 was done on 1 patient. RESULTS: All patients had a pure lower motor neuron syndrome with onset to death in 9-15 months. A Gly41Ser mutation in SOD1 was established. In silico modeling suggested that this mutation can have a more deleterious effect than a Gly41Asp mutation. CONCLUSION: The more rapid course of ALS with the Gly41Ser SOD1 mutation is confirmed in a distinct ethnic group.