MMP12 and infection: When evaluating other MMP polymorphisms, ever infection with HP was also associated with a significantly decreased EA risk in the subset of patients who carried the wild-type genotypes, MMP3 −1171 6A/6A (AOR 0.04, 95% CI=0.002–0.9, P=0.04; 27 cases/29 controls) and MMP12 −82 A/A (AOR 0.44, 95% CI=0.2–0.8, P=0.02; 75 cases/79 controls), but not for their corresponding variant genotypes.