Qin et al.[37] established a cathepsin S/ApoE double knockout mouse model using AngII infusion, and found that the cathepsin S-knockout mice showed significantly reduced AAA incidence (1/8 of that observed in ApoE-/- mice), and a 47% (0.86 mm) decrease in abdominal aortic diameter[7]. The gene discussed is APOE; the disease is triple-A syndrome.