However, proprotein convertase subtilisin/kexin type 9 (PCSK9), which is overexpressed in patients with familial hypercholesterolemia, competitively binds to the LDLR and inhibits the rearrangement of the LDLRs recycled to the plasma membrane, leading to high levels of LDL-C in the plasma [5,6]. This evidence concerns the gene PCSK9 and familial hypercholesterolemia.