Ldlr−/− mice and Apoe−/− mice with an additional dominant-negative mutant of the gene Clock (ClockΔ19) exhibit enhanced levels of atherosclerosis compared with Ldlr−/− (1.6–4-fold) and Apoe−/− (22–34-fold) animals, respectively.117 Besides higher plasma lipid levels, higher inflammatory cytokines, including IL-12 and G-CSF (granulocyte colony-stimulating factor), were found in the plasma of ClockΔ19 Apoe−/− mice compared with Apoe−/− mice alone. This evidence concerns the gene APOE and atherosclerosis.