For IL-27 gene polymorphisms, a study involving a Chinese Han population reported that rs153109, rs17855750, and rs181206 polymorphisms did not correlate with RA risk, whereas frequency of haplotype GTC [rs153109 (G) + rs17855750 (T) + rs181206 (C)] was higher in patients with RA, and frequency of haplotype GTT [rs153109 (G) + rs17855750 (T) + rs181206 (T)] was lower in patients with RA than that in controls, respectively (163) (Table 2). Here, IL27 is linked to rheumatoid arthritis.