Out of ten patients presenting a positive ELISA result, six had GPA and all of them had a positive PR3-ANCA, one had MPA and tested positive for both MPO- and PR3-ANCA, one patient with type 1 AIH had a positive MPO-ANCA, and two UC patients had positive PR3-ANCA. The gene discussed is PRTN3; the disease is granulomatosis with polyangiitis.