SOD1 and amyotrophic lateral sclerosis: There are currently over 185 mutations throughout the SOD1 gene that have been associated with ALS, some of which cause more aggressive forms of disease (e.g., A4V, H43R, L84V, G85R N86S, and G93A) and others that lead to slower disease progression (e.g., G93C, D90A, and H46R) [91].