Protein aggregates can be composed of different proteins: SOD1 [present only in family forms of ALS (Rosen et al., 1993; Blokhuis et al., 2013); TDP-43 (Arai et al., 2006), FUS (Neumann et al., 2009b; Doi et al., 2010), optineurine, ataxin-2, and ubiquiline-2 (Blokhuis et al., 2013)]. Here, SOD1 is linked to amyotrophic lateral sclerosis.