SOD1 and amyotrophic lateral sclerosis: More than 160 different mutations to the gene encoding for SOD1 have been reported (Rosen, 1993; Al-Chalabi et al., 2012), accounting for approximately 20% of all familial forms of ALS (FALS; Andersen and Al-Chalabi, 2011; Robberecht and Philips, 2013).