title: Low expression myeloperoxidase genotype negatively associated with Helicobacter pylori infection.
abstract: Our previous study revealed that a polymorphism of the interleukin (IL) 1B gene, encoding the pro-inflammatory cytokine IL-1 beta, influenced the prevalence of persistent Helicobacter pylori (HP) infection. In this paper, a polymorphism of another inflammation-related enzyme, myeloperoxidase (MPO), was examined with respect to association with the HP infection. The polymorphism is due to a G-to-A transition at - 463 in the promoter region of MPO. The G allele is the wild type with normal expression, while the A allele is a low expression allele. The subjects were 241 non-cancer outpatients (118 males and 123 females) aged 39 to 69 who participated in an HP eradication program at Aichi Cancer Center Hospital. High-molecular weight Campylobacter-Associated-Protein (HM-CAP) ELISA (Enteric Products Ins., Westbury, NY) was used for the identification of HP-infected participants. The frequency was 79.7% (192 / 241) for the GG genotype, 19.5% (47 / 241) for the GA genotype, and 0.8% (2 / 241) for the AA genotype. The sex-age-adjusted odds ratio (OR) relative to GG was 0.69 (95% confidence interval (CI), 0.35 -- 1.35) for individuals with the A allele, but among male participants the OR was 0.31 (0.11 -- 0.84). Subgroup analysis revealed significantly reduced ORs with the GA / AA genotypes for current smokers (0.19, 0.04 -- 0.96), and for those who were occasional / no milk drinkers (0.25, 0.09 -- 0.72). These findings are consistent with the results for IL-1B in our earlier study, suggesting that inflammatory responses in the gastric mucosa may influence persistent HP infection, and that smoking and milk intake may be effect-modifiers.
authors.affiliation: Division of Epidemiology and Prevention, Aichi Cancer Center, Chikusa-ku, Nagoya 464-8681, Japan. nhamajim@aichi-cc.pref.aichi.jp
authors.forename: N
authors.initials: N
authors.lastname: Hamajima
authors.forename: K
authors.initials: K
authors.lastname: Matsuo
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: T
authors.initials: T
authors.lastname: Nakamura
authors.forename: A
authors.initials: A
authors.lastname: Matsuura
authors.forename: K
authors.initials: K
authors.lastname: Tajima
authors.forename: S
authors.initials: S
authors.lastname: Tominaga
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D004032:Diet; D015444:Exercise; D005260:Female; D005638:Fruit; D015870:Gene Expression; D005838:Genotype; D016481:Helicobacter Infections / Q000201:enzymology / Q000235:genetics*; D016480:Helicobacter pylori / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008019:Life Style; D008297:Male; D008875:Middle Aged; D008892:Milk; D016017:Odds Ratio; D009195:Peroxidase / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011401:Promoter Regions, Genetic; D012907:Smoking
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D009195:Peroxidase