While the isolated loss of Dab2 only mildly affects serum cholesterol levels [232], the combined deletion of Dab2 and ARH increased the hypercholesterolemia to the level found upon LDLR loss of function [231] suggesting that Dab2 and ARH act in parallel in LDLR endocytosis. This evidence concerns the gene LDLR and familial hypercholesterolemia.