PSMA6 and chronic obstructive pulmonary disease: Laennec [26] identified for the first time this condition, which favors the onset of bronchiectasis in a wide group of conditions including: pulmonary structural alterations—typical of Williams-Campbell syndrome [27], Mounier-Kuhn syndrome [28] and Ehlers-Danlos syndrome [29]—single bronchial obstruction—as in case of neoplasms or foreign bodies—and, finally, obstructive diseases—such as asthma [30], chronic obstructive pulmonary disease (COPD) [31], and alpha-1-antitrypsin deficiency [32].