We have shown that the Mmp12 gene is critical for triggering the in utero SHS-aggravated elastase-induced emphysema (Figures 2–4), HDM-induced asthma (Figures 5–7), and urethane-induced lung cancer (Figures 8–13), with significant up-regulation of this gene in the lungs of the exposed female mouse offspring (Figures 14A,C,E). This evidence concerns the gene MMP12 and pulmonary emphysema.