Hazlet et al. and Yu et al. evaluated the functional outcomes of R381Q (G1142A-rs11209026) polymorphism in RA, observing an altered function of IL-23, which determines a lowered production of Th17 cells and IL-17 upon IL-23 stimulation, suggesting a protective role for rs11209026 in some autoimmune diseases [57]. This evidence concerns the gene IL23A and rheumatoid arthritis.