SR and D-serine are involved in both the pre-symptomatic and progressive phases of ALS in G93A Cu, Zn-superoxide dismutase (SOD-1) mice, the standard model of ALS transgenic mice, suggesting a link between mutant SOD-1 and D-serine increase in ALS (Sasabe et al., 2012). Here, SOD1 is linked to amyotrophic lateral sclerosis.