Proprotein convertase subtilisin/kexin type 9 (PCSK9) is an enzyme that plays a key role in regulating the circulating low density lipoprotein cholesterol (LDL-C). Among PCSK9 variants, while gain-of-function mutations aggravate degradation of LDL receptors, leading to familial hypercholesterolemia (FH), whereas loss-of-function increase receptor levels, lower and prevent coronary heart disease...