HLA-DRB1 and Peptic ulcer: The aim of this study was to explore possible associations between IL-1B-31T/C, IL1RN VNTR alleles, IFNGR1-56C/T, the HLA DRB1 alleles, blood group and life style factors and H. pylori infection, the occurrence of peptic ulcer, grade of gastric mucosal inflammation, atrophy, and IM in a prospective population based cohort in Sweden.