Minireview: ARSENIC, GSTO2 ASN142ASP POLYMORPHISM, HEALTH AND TREATMENT

Arsenic is a natural metallic element found in low concentrations in virtually every part of the environment, including waters and foods. The ingestion of arsenic by humans can cause a variety of disorders. Glutathione S-transferase omega (GSTO) is a member of phase II xeno-biotic metabolizing enzymes. GSTO2 (a member of GST omega) participates in detoxifica-tion of inorganic arsenic. In human, the A>G transition at nucleotide position 424 of GSTO2 was reported. This variation causes an Asn142Asp substitution. The Asp142 allozyme was expressed at approximately 80 % of the level of Asn142 allozyme. It is hypothesized that the GSTO2 polymorphism may alter the risk of several diseases which are related to chronic arse-nic poisoning. On the other hand, because arsenic trioxide is used for treatment of acute pro-myelocytic leukemia; it is possible that Asn142 allozyme may decrease the therapeutic ef-fect(s) of the drug