During the last 20 years, the most popular animal model of ALS has been the superoxide dismutase 1 G93A transgenic mouse (SOD1G93A), overexpressing human SOD1 with a causative mutation (a glycine to alanine substitution at position 93), which results in a toxic gain of SOD1 function (Dal Canto and Gurney 1994; Achilli et al. 2005). The gene discussed is SOD1; the disease is amyotrophic lateral sclerosis.