We sought to determine contributions of circulating monocytes to atherosclerosis associated with HTG in combined hyperlipidemia, created by transgenic expression of human apoCIII in Ldlr<sup>-/-</sup> mice (Ldlr<sup>-/-</sup>ApoCIIItg) fed Western high-fat diet (WD). This evidence concerns the gene APOC3 and hyperlipidemia.