Through colocalisation analysis, we found colocalisation‐mapped genes, including BAG6, GPSM3, PRRC2A, PSMB8, RNF5, NELFE, AGER, PBX2 and AIF1, which are common to RA, AS, SLE and SS (Figure 5a). The gene discussed is PRRC2A; the disease is rheumatoid arthritis.