In addition, TT genotype carriers showed a percentage of functional class III + IV and a DAS28 of ≥3.20, which was in line with the findings by Paradowska-Gorycka et al. However, we did not examine VEGFR2 serum levels in patients with RA and analyzed the association between VEGFR2 gene polymorphisms and its concentration. The gene discussed is KDR; the disease is rheumatoid arthritis.