By ELISA, 38/142 (26.8%) of the PSC & IBD patients [PSC-CD 6/27 (22.2%), PSC-UC 32/111 (28.8%), PSC-IBD-U 0/4] were positive for PR3-ANCA compared to 10/62 (16.1%) of the PSC & no associated IBD patients (p = 0.14). The gene discussed is PRTN3; the disease is inflammatory bowel disease.