In response to bleomycin instillation, CKO mice showed attenuated bleomycin-lung fibrosis versus controls, as indicated by constricted fibrotic foci formation and parenchymal distortion, which was in line with decreases in the semiquantitative fibrotic score, hydroxyproline content and the expressions of α-SAM, collagen I and Cyclin D1 (Fig. 2C–F, Additional file 1: Fig. S2D). The gene discussed is CCND1; the disease is pulmonary fibrosis.