Proteomic analysis also have been applied to identify serum biomarkers for IPF, they found that 97 out of total 394 proteins were associated with IPF, C-reactive protein (CRP), fibrinogen- α chain, haptoglobin, and kininogen-1 were useful candidate biomarkers for IPF [17]. The gene discussed is KNG1; the disease is idiopathic pulmonary fibrosis.