T-lymphocytes are involved in the production of a wide range of proinflammatory cytokines, predominantly in the tumour necrosis factor (TNF) and interleukin (IL) superfamilies, as well as growth factors.5 B-lymphocytes are associated with the production of autoantibodies, such as rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (ACPA).6 RA is a heterogeneous condition. This evidence concerns the gene TNF and rheumatoid arthritis.