To further explore the relationship between these four hub genes (IFIT2, IFIT3, RSAD2, and PAPR14) and clinical risk factors (age, gender, ILD, forced vital capacity (FVC)% predicted, DLCO% predicted) in patients with SSc-PAH, we applied the ULR analysis in duplication cohort. The gene discussed is IFIT2; the disease is systemic sclerosis.