After integrating the data of SLE, RA, and GO, it was found that several SNPs had intersections, including rs11571315, rs733618, rs4553808, rs16840252, and rs11571319 of CTLA4 and rs36084323 of PDCD1, which indicated that these three diseases had a partial genetic background. The gene discussed is CTLA4; the disease is systemic lupus erythematosus.