PCSK9 and familial hypercholesterolemia: Familial hypercholesterolemia (FH; OMIM#143890) is an autosomal-dominant disease caused by a deficiency in low-density lipoprotein (LDL) receptor (ADH1) activity or in LDL-related genes (ApoB and PCSK9), which leads to obviously elevated LDL cholesterol (LDL-C) and triglyceride concentrations [10,84].