Further analysis revealed that the levels of MPO‐DNA complexes and NE‐DNA complexes were higher in RA patients with ACPA‐SP when compared to ACPA‐MP (1.05 [0.50–1.53] vs 0.50 [0.40–0.90] and 1.10 [0.78–2.75] vs 0.60 [0.40–0.90], RU, p = 0.048 and p = 0.022, Figure 1C,D), which were consistent with our previous results. This evidence concerns the gene MPO and rheumatoid arthritis.