Among the 14 genes, eight genes (CCR5, CCL5, CXCL9, CXCL10, CXCL13, PNOC, TLR8, and CD52) with AUC more than 0.80 were considered as hub genes, indicating that they have the capability to diagnose RA patients with excellent specificity and sensitivity. Here, CXCL9 is linked to rheumatoid arthritis.