HLA-DRB1 and synovial sarcoma: Of these candidates, four genes (STAT4, GTF2I, HLA-DPB1, and HLA-DRB1) had been reported their association with pSS in the original GWAS dataset6, and gene PTTG1 (pituitary tumor-transforming 1) had been reported as suggestive association (rs2431098, allelic meta P-value = 2.28 × 10−7; rs2431697, allelic meta P-value = 3.76 × 10−6) with SS in another GWAS study of SS in European descent5.