PCSK9 and atherosclerosis: In line with these suggestions that PCSK9 exerts LDL-R-independent effects related to atherosclerosis, a triple knockout mouse with PCSK9−/−, LDL-R−/−, and ApoB−/− revealed less atherosclerosis than an LDL-R−/− and ApoB−/− double knockout mouse without any differences in cholesterol levels (Sun et al., 2018).