CXCR5 and synovial sarcoma: In addition, six non-HLA regions that surpassed the suggestive threshold (Pmeta < 5 × 10–5) were also shown to be involved in SS, including IRF5, STAT4, BLK, IL-12A, TNIP1, and CXCR5, with the expression of IRF5 and STAT4 being the most significant contributors after HLA regions (Table 1) (49).