SOD1 and amyotrophic lateral sclerosis: As the etiology of ALS is still unclear, animal models are based on gene mutations which are found in familial cases: Cu–Zn superoxide dismutase gene SOD1, C9ORF72, PGRN, TBK1, TARDBP, and FUS genes (Freischmidt et al. 2015; Al-Chalabi et al. 2016; Lutz 2018).