SOD1 and amyotrophic lateral sclerosis: ALS can also be genetically categorized as being either sporadic ALS (SALS) that represents 90–95% of all diagnoses and in which there is no known direct genetic contribution to the disease, or familial ALS (FALS) that makes up the remaining 5–10% of all cases where known genetic mutations such as in SOD1, TDP-43, FUS, and C9ORF72 predominate (Zarei et al., 2015).