One plausible explanation for the pleiotropic effects of this region is that it hosts the Hedgehog (Hh)-interacting protein (HHIP) gene, which is associated with multiple pulmonery traits, such as FEV1/FVC ratio, chronic obstructive pulmonary disease (COPD) and lung cancer58–61. Here, HHIP is linked to chronic obstructive pulmonary disease.