TARDBP and amyotrophic lateral sclerosis: ALS can be either sporadic (sALS) or familial (fALS), and four genes (superoxide dismutase 1 (SOD1), TAR DNA binding protein (TARDBP), fused in sarcoma (FUS), and C9ORF72) are causally linked to the pathogenesis, and account for the majority of fALS cases.