Moreover, we reported the most frequent allele identified in patients with severe hypercholesterolemia was LDLR-Ava II polymorphism AA compared to that in subjects with normocholesterolemia, indicating that LDLR-Ava II polymorphism AA is a genetic marker of susceptibility to severe hypercholesterolemia in Kurdish population. This evidence concerns the gene LDLR and familial hypercholesterolemia.