ABCG1 and atherosclerosis: We attribute the lack of an effect of SMC-Abca1/Abcg1 deficiency on atherosclerosis in the thoracic aorta to thoracic aorta SMCs not showing ER stress or transdifferentiation due mainly to CE accumulation and the lack of an effect of SMC-Abca1/Abcg1 deficiency on atherosclerotic lesion size and composition to low expression of Abca1/Abcg1 in intimal SMCs of Ldlr−/− mice.