SOD1 and amyotrophic lateral sclerosis: Dynactin heavy (DCTN1) and light (DCTN3) subunits were studied in the CNS of humans with sporadic ALS (SALS), mice with hSOD1G93A (SOD1/+), Dync1h1 (Cra1/+), and double (Cra1/SOD1) mutation at presymptomatic and symptomatic stages.