Superoxide dismutase [Cu-Zn] also known as superoxide dismutase 1 or hSod1 is an enzyme that in humans is encoded by the SOD1 gene, located on chromosome 21. SOD1 is one of three human superoxide dismutases.[5][6] It is implicated in apoptosis, familial amyotrophic lateral sclerosis and Parkinson's disease.[6][7]