The elevated expression of CYP2E1, a microsomal oxidase involved in fatty acid ω-oxidation, as well as CYP4A, has been shown to be largely responsible for the pathogenesis of liver disease in patients with nonalcoholic steatohepatitis and plays a key role in the development of liver injury by initiating lipid peroxidation [3-7]. The gene discussed is CYP2E1; the disease is liver disorder.