Abbreviations: RA = rheumatoid arthritis, IFX = Infliximab, ETA = Etanercept, ADA = Adalimumab, RTX = Rituximab, ESR = erythrocyte sedimentation rate, CRP = reactive C protein, DAS 28 = disease activity score, anti TNF = inhibitor of tumor necrosis factor. This evidence concerns the gene CRP and rheumatoid arthritis.