discovered that while smoke exposure or Ang II treatment alone had minimal effects on Mmps expression levels in ApoE(−/−) mice, the combined exposure significantly upregulated the gene expression of Mmp‐2, ‐3, ‐8, ‐9, and ‐12 in abdominal aorta, leading to accelerated AAA formation and severity.140. This evidence concerns the gene MMP2 and triple-A syndrome.