Since ABCA7 deficiency in macrophages led to a significant up-regulation of ABCA1, we compared the effects of combined macrophage ABCA1 and ABCA7 deletion with single macrophage deficiencies of these transporters on lipid metabolism and atherosclerosis in vivo by means of the bone marrow transplantation (BMT) strategy. This evidence concerns the gene ABCA1 and atherosclerosis.