DPP9 and idiopathic pulmonary fibrosis: COLOC demonstrated moderately strong colocalization between the disease GWAS and IPF cases DPP9-eQTL signals (PP4 = 0.874 with IPF GWAS; 0.873 with COVID-19 GWAS) and weaker colocalization between the GWAS and control eQTL signals (PP4 = 0.661; 0.640; Figure 5E–F; Table S9).