When selecting samples negative for all ACPA specificities irrespective of anti-CCP2 antibodies, the frequencies of positivity for anti-CarP antibodies were 2.8%, 5.8% and 13.3% in controls, pre-symptomatic individuals and RA-patients, respectively (for further details on the relationships to sub specificities, see Table 3). The gene discussed is PRTN3; the disease is rheumatoid arthritis.