Glutathione peroxidase 1 also known as GPx-1 is an enzyme that in humans is encoded by the GPX1 gene. Two alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. This gene encodes a member of the glutathione peroxidase family, consisting of eight 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. Glutathione peroxidase 1 is characterized in a polyalanine sequence polymorphism in the N-terminal region, which includes three alleles with five, six or seven alanine (Ala) repeats in this sequence. The allele with five Ala repeats is significantly associated with breast cancer risk.
