As for proinflammatory cytokines, RA patients generally had higher values than controls for GM-CSF, IL-1ß, IL-12, IL-13, IL-2, IL-5, IL-6, TNF-α, IL-10, IL-17A, IL-21, IL-22, IL-23, IL-27, IL-9, IL1α, IL-15, IL-1RA, IL-7, and TNF-ß. This evidence concerns the gene IL13 and rheumatoid arthritis.