SOD1 and amyotrophic lateral sclerosis: Mutations in superoxide dismutase 1 (SOD1) were the first to be identified in patients with ALS in 1993 (Rosen et al., 1993), but after >25 years of research, we still do not know how mutations in SOD1 or those identified in other genes lead to selective neuronal death, or what shared or distinct mechanisms are at play between different genetic forms (Mejzini et al., 2019; Taylor et al., 2016).