TGFB1 and bronchiectasis: Although the number of patient is relatively small for a genetic polymorphism study, our results demonstrate that bronchiectasis patients with MMP-1(-1607G) polymorphism are more likely to develop a greater extent of lung fibrosis or airway destruction, which may be attributable to the production of MMP-1 and TGF-β1 activity and leading to proteolytic destruction of matrix.