Among the polymorphisms found more frequently in AS patients with arthritis, JAK2 rs7857730, IL-23R rs11209008 and rs10489630, CYP1B1 rs1056836, NELL1 rs8176786, KL rs564481, MEFV rs224204, IL-2RB rs743777, and IL-1A rs1800587 have been described [70]. Here, NELL1 is linked to arthritic joint disease.