The most well-known example is “halothane hepatitis.” Halothane (CHClBrClF3), an anesthetic ethane, is metabolized by CYP2E1 to produce trifluoroacetic adducts, and the repeated exposure produced CYP2E1 autoantibodies (autoimmune antibodies), which are believed to be the major cause of hepatitis (Eliasson and Kenna 1996; Kenna and Neuberger 1995). Here, CYP2E1 is linked to Hepatitis.