Pathogenic variants in superoxide dismutase 1 (SOD1), TAR DNA binding protein (TARDBP), fused in sarcoma (FUS) and chromosome 9 open reading frame 72 (C9ORF72), the most common ALS-associated genes, account for approximately 60% of familial cases and about 10% of sporadic ALS. Here, SOD1 is linked to amyotrophic lateral sclerosis.