ABCA1 and atherosclerosis: Surprisingly though, studies involving the whole-body and tissue-specific deletion and overexpression of ABCA1 and ABCG1 have been conflicting when evaluating whether these two transporters protect against atherosclerosis [10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29].