No difference between Italian ALS patients with or without H63D (3.4 vs. 3.0 years; p = n.s.) or between Sardinian ALS patients with or without H63D (3.5 vs. 4.7 years; p = n.s.). Longer disease duration for Italian ALS patients carrying SOD1 mutations with H63D compared to without (15.3 vs. 2.1 years; p = 0.04). No difference in site of onset between ALS patients with or without H63D (26.3% vs. 26.9% bulbar; p = 0.91). Here, SOD1 is linked to amyotrophic lateral sclerosis.