C9orf72 and amyotrophic lateral sclerosis: Mutations observed in several genes related to ALS such as SOD1(Rosen et al., 1993), FUS (Kwiatkowski et al., 2009), C9ORF72 (DeJesus-Hernandez et al., 2011, Renton et al., 2011), ATXN2 (Elden et al., 2010), OPTN (Maruyama et al., 2010), VCP (Johnson et al., 2010), PFN1 (Wu et al., 2012), MATR3 (Johnson et al., 2014), SETX (Hirano et al., 2011), UBQLN2 (Deng et al., 2011).