Restriction fragment length polymorphisms (RFLPs) of apolipoprotein B (XbaI, EcoRI), apolipoprotein A-I (PstI, MspI), and cholesteryl ester transfer protein (CETP) (EcoNI, TaqIA, TaqIB) genes were examined in a series of 210 cholecystectomy patients operated on for symptomatic gallbladder disease and in 92 healthy controls.