SOD1 and amyotrophic lateral sclerosis: Other genetic variants associated with ALS survival include Asp91Ala, one of the most common mutations in SOD1 that is associated with a long survival when the locus had homozygous genotype, while that of affected heterozygotes varies; and the rs12608932 located in intron 21 of the UNC13A gene that is associated with an increased risk and shorter survival of ALS patients (Daoud et al., 2010; Diekstra et al., 2012; Harms and Baloh, 2013; Cady et al., 2015; Gaastra et al., 2016; Yang et al., 2019).