Familial hypercholesterolemia is characterized by increased LDL levels due to changes in hepatic LDL-R (familial hypercholesterolemia), changes in the apolipoprotein B100 protein receptor on the LDL particle surfaces (apolipoprotein B-100 deficit), or gain in the proprotein convertase subtilisin/Kexin type 9 function, which is involved in LDL-R degradation [35]. The gene discussed is LDLR; the disease is familial hypercholesterolemia.