Furthermore, disease-related phenotypes were not observed in transgenic mice expressing human SOD1 that has multiple mutations including those at copper and zinc binding sites (H46R/H48Q/H63G/H71R/H80R/H120G) and two free Cys residues (C6G/C111S) with an ALS-linked mutation, H43R, and co-expression of wild-type human SOD1 did not cause the disease [35]. This evidence concerns the gene SOD1 and amyotrophic lateral sclerosis.