The East Asian-type CagA is associated with a more robust mucosal inflammatory reaction than Western-type CagA and epidemiological studies in Thailand, South Korea, and Okinawa, Japan have shown East Asian-type CagA strains correlate with an increased risk of peptic ulcer or gastric cancer compared with those infected with Western-type CagA strains14, 15, 16. This evidence concerns the gene S100A8 and peptic ulcer disease.