the present invention discloses the identification of a human hypercholesterolemia causal gene , which can be used for the diagnosis , prevention and treatment of hypercholesterolemia , more particularly familial hypercholesterolemia , as well as for the screening of therapeutically active drugs . the invention more specifically disclosed that mutations in the pcsk9 gene encoding narc - 1 causes autosomal dominant hypercholesterolemia and represent novel targets for therapeutic intervention . the invention can be used in the diagnosis of predisposition to , detection , prevention and / or treatment of coronary heart disease and , cholesterol , lipid and lipoprotein metabolism disorders , including familial hypercholesterolemia , atherogenic dyslipidemia , atherosclerosis , cardiovascular diseases .