Although the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and disease activity score (DAS) are currently used to estimate RA, several studies have reported the limitations of these markers, such as flooring effects at lower disease activity.[4–6] Ultrasound and magnetic resonance imaging have been reported to show synovial inflammation, even when the ESR, CRP and DAS have reached the lowest or near normal levels.[7,8] However, these techniques are expensive and time consuming. This evidence concerns the gene CRP and rheumatoid arthritis.