APOE and atherosclerosis: We analyzed the LDL-C level between Apoe single-gene-knockout and Apoe−/−Ldlr−/− double-gene-knockout animals on a HFD, and found that the LDL-C level was significantly higher in double-knockout animals, suggesting that lower LDL-C could contribute to resistance of single-gene Apoe-knockout mice to atherosclerosis.