Glutathione peroxidase 2（GPX2) is a member of the glutathione peroxidase family， consisting of 8 known glutathione peroxidases（Gpx1-8) in humans. Glutathione peroxidase functions in the detoxification of hydrogen peroxide， and is one of the most important antioxidant enzymes in humans. GPX2 may have a major role in protecting mammals from the toxicity of ingested organic hydroperoxides. GPX2 is one of only a few proteins known in higher vertebrates to contain selenocysteine， which appears at the active site of glutathione peroxidase and is coded by the nonsense（stop) codon TGA.
