SOD1 and amyotrophic lateral sclerosis: While most cases of ALS are sporadic, about 10% are familial forms caused by mutations in different genes (Hardiman et al., 2017), including those encoding the cytoplasmic enzyme superoxide-dismutase 1 (Rosen et al., 1993), the RNA-binding proteins TAR DNA-binding protein 43 (Kabashi et al., 2008) and fused in sarcoma/translocated in liposarcoma (FUS) (Kwiatkowski et al., 2009; Vance et al., 2009).