A vast majority of the patients with strong IgG anti-modified peptide (Carb, Lys(Ac), Orn(Ac)) reactivity were CCP2 positive and the frequency of mod-Vim positivity was significantly higher in CCP2+ RA compared to CCP2- RA (Cit 88% vs. 11%; Orn(Ac) 76% vs. 7.6%; Carb 61% vs. 6%; Lys(Ac) 43% vs. 4.4%). This evidence concerns the gene AGBL2 and rheumatoid arthritis.