MPO activity, which is accepted as an indicator of neutrophil infiltration of the inflamed tissue, was significantly higher in gastric tissues of the ethanol-induced ulcer group than in the control group (51.3 ± 5.8 U/g tissue vs. 16.3 ± 2.3 U/g tissue; p < 0.001). The gene discussed is MPO; the disease is ulcer disease.