APOE and atherosclerosis: Previously, we have shown that apolipoprotein E-null mice on a C57BL/6J and a 129S6 genetic background (B6-apoE and 129-apoE) develop atherosclerosis differently in the aortic arch and the aortic root area: in the arches, 129-apoE mice form larger plaques than B6-apoE mice, whereas plaques in the roots are smaller in 129-apoE than in B6-apoE [4].