title: Immunogenetic analysis of the human leukocyte antigen DQA1 locus in patients with duodenal ulcer or chronic atrophic gastritis harbouring Helicobacter pylori.
abstract: OBJECTIVE
  To examine the human leukocyte antigen (HLA)-DQA1 locus in patients harbouring Helicobacter pylori with chronic atrophic gastritis or duodenal ulcer as part of an investigation into immunogenetic differences in the host.
  
  
  METHODS
  We examined 116 patients harbouring H. pylori (55 patients with chronic atrophic gastritis, 61 with duodenal ulcers) and 28 H. pylori-negative healthy controls for HLA-DQA1 genotypes. H. pylori infection was determined by culturing biopsy samples from the gastric body and antrum and by enzyme-linked immunosorbent assay. HLA-DQA1 typing was carried out by the polymerase chain reaction-restriction fragment length polymorphism method.
  
  
  RESULTS
  The allele frequency of DQA1*0102 was significantly higher in H. pylori-negative controls (0.250) than in H. pylori-positive duodenal ulcer patients (0.090). In contrast, the allele frequency of DQA1*0301 was significantly lower in H. pylori-negative controls (0.214) than in H. pylori-positive duodenal ulcer patients (0.418).
  
  
  CONCLUSIONS
  These results suggest that there are genetic differences in the HLA-DQA1 locus between H. pylori-positive duodenal ulcer patients and H. pylori-negative healthy controls.
authors.affiliation: Second Department of Internal Medicine, Fukui Medical School, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Azuma
authors.forename: Y
authors.initials: Y
authors.lastname: Ito
authors.forename: H
authors.initials: H
authors.lastname: Miyaji
authors.forename: M
authors.initials: M
authors.lastname: Dojyo
authors.forename: Y
authors.initials: Y
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Hirai
authors.forename: S
authors.initials: S
authors.lastname: Ito
authors.forename: T
authors.initials: T
authors.lastname: Kato
authors.forename: Y
authors.initials: Y
authors.lastname: Kohli
mesh_terms: D000328:Adult; D000483:Alleles; D004381:Duodenal Ulcer / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D005260:Female; D005757:Gastritis, Atrophic / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D005838:Genotype; D006683:HLA-DQ Antigens / Q000235:genetics*; D059848:HLA-DQ alpha-Chains; D016481:Helicobacter Infections / Q000150:complications / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D016480:Helicobacter pylori / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; C069050:HLA-DQA1 antigen