Recurrent G41S mutation in Cu/Zn superoxide dismutase gene (SOD1) causing familial amyotrophic lateral sclerosis in a large Polish family

Mutations in the superoxide dismutase-1 (SOD1) gene have been found in 1223% of patients with a diagnosis of ALS. Here we describe a large ALS Polish family with a branch in France, carrying a G41S mutation in the SOD1, and characterized by an early onset of the disease and extremely short survival time. The mutation has been initially detected in Italian ALS families with common founder effect. However, in the Polish population the G41S mutation most probably originated from an independent mutation event, as indicated by haplotype analysis. Collected data support the hypothesis that a SOD1 mutation is not the sole factor determining the clinical ALS phenotype.