CYP2C8 encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This protein localizes to the endoplasmic reticulum and its expression is induced by phenobarbital. The enzyme is known to metabolize many xenobiotics, including the anticonvulsive drug mephenytoin, benzo(a)pyrene, 7-ethyoxycoumarin, and the anti-cancer drug taxol. This gene is located within a cluster of cytochrome P450 genes on chromosome 10q24. Several transcript variants encoding a few different isoforms have been found for this gene. CYP2C9 encodes a member of the cytochrome P450 superfamily of enzymes. This protein localizes to the endoplasmic reticulum and its expression is induced by rifampin. CYP2C18 encodes a member of the cytochrome P450 superfamily of enzymes. This protein localizes to the endoplasmic reticulum but its specific substrate has not yet been determined. CYP2C19 encodes a member of the cytochrome P450 superfamily of enzymes. This protein localizes to the endoplasmic reticulum and is known to metabolize many xenobiotics, including the anticonvulsive drug mephenytoin, omeprazole, diazepam and some barbiturates.