The risk of coronary heart disease and myocardial infraction is increased by the appearance of autosomal dominant hypercholesterolemia, which occurs in three forms: (1) familiar hypercholesterolemia resulting from a mutation in the LDLR gene, (2) familial defective apolipoprotein B resulting from a mutation in the APOB gene, and (3) hypercholesterolemia, autosomal dominant, 3, which is caused by one of three missense mutations in the PCSK9 gene. This evidence concerns the gene PCSK9 and familial hypercholesterolemia.