Bártholo TP, et al. - In this cross-sectional analysis enrolling 81 patients diagnosed with COPD according to the criteria of the Global Initiative for Chronic Obstructive Lung Disease, researchers intended to correlate three polymorphisms of the Hedgehog Interacting Protein (HHIP) gene with the three main phenotypes of the chronic obstructive pulmonary disease (frequent exacerbator (FE), asthma/COPD overlap (ACO), and emphysema with hyperinflation). In the group of people with COPD and emphysema-hyperinflation phenotype vs those in the FE phenotype and individuals with ACO, a rise in the frequency of the A allele of the rs13118928 HHIP gene polymorphism was seen. However, the presence of A allele was more commonly detected in individuals with emphysema-hyperinflation phenotype. Findings are suggestive of a possible link between the presence of the A allele in the rs13118928 polymorphism of the HHIP gene and the emphysema-hyperinflation phenotype.