TET1 and TET3 showed the most marked difference between RA patients and controls (TET1, Fig. 3a; mean = 2.9, 95 % CI = 2.1–4.8 vs. 1.9, 95 % CI = 1.6–2.3; P = 0.0044; and TET3, Fig. 3c; mean = 2.0, 95 % CI = 1.7–2.3 vs. 1.35, 95 % CI = 1.15–1.6; P = 0.0014), but also TET2 (Fig. 3b; mean = 2.5, 95 % CI = 1.9–3.2 vs. 1.8, 95 % CI = 1.5–2.2; P = 0.019) was increased in monocytes of the patients with RA. This evidence concerns the gene TET2 and rheumatoid arthritis.