By applying the HEIDI test (P > 0.05), we found that rs9277410 in HLA-DPB2, rs4836834 in TRAF1, rs2952151 in PGAP3 and rs9303280 in GSDMB may be causal variants that affect both gene expression and RA (Table 2). Here, GSDMB is linked to rheumatoid arthritis.