Further morphological analysis revealed that HO-1 deficiency significantly increased aneurysm along the aortic length from 12±3% to 41±9% (P < 0.05) and aneurysmal 2-dimensional area from 6±2 mm2 to 16±4 mm2 (P < 0.05) (Figure 2A, 2E, and 2F). This evidence concerns the gene HMOX1 and aneurysm.