SOD1 and amyotrophic lateral sclerosis: Although the preponderance (90%) of ALS cases is sporadic (sALS), several genes have been identified as responsible for genetic heritability (fALS, 10%), namely, superoxide dismutase 1 (SOD1), chromosome 9 open reading frame 72 (C9orf72), fused in sarcoma (FUS), and transactive response DNA-binding protein 43 (TARDBP) [73,74].