In contrast to previous reports on case-control studies that showed an association of MMP1, MMP9 and MMP12 with COPD, emphysema, decreased levels of FEV1, and/or excess decline in FEV1 [12,14]., we found no indication whatsoever for a role of MMP1, MMP9 or MMP12 in the development of (mild to moderate) COPD or FEV1 decline in our prospective population studies. This evidence concerns the gene MMP9 and pulmonary emphysema.