title: Genotypes of the Helicobacter pylori vacA signal sequence differ with age in Korea.
abstract: BACKGROUND
  Studies on Helicobacter pylori genotypes have focused on adults in developed countries, and data on the genotypes of Helicobacter pylori recovered from the children are rare.
  
  
  METHODS
  One hundred and twenty-eight biopsy samples from patients with H. pylori infection were studied. The patients' ages ranged from 9 to 83 years. PCR analysis for vacA genotypes was performed using DNA extracted from biopsy specimens.
  
  
  RESULTS
  Genotyping of the s-region showed s1a in 33 (25.8%) samples and s1c in 82 (64.1%) samples. When the specimens were grouped by age, the distribution of s-region genotype was found to be significantly different between groups (p = .002). The prevalence of s1a was 45.2% in patients < 20 years old, but 14.9% in patients > or = 50 years old. On the other hand, the prevalence of s1c or recombinant s1a-s1c was higher in those > or = 50 years old. The distribution of the m-region did not differ significantly with age (p = .110).
  
  
  CONCLUSIONS
  Strain populations infecting Korean adults and children differ.
authors.affiliation: Department of Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jun Haeng
authors.initials: JH
authors.lastname: Lee
authors.forename: Yon Ho
authors.initials: YH
authors.lastname: Choe
authors.forename: Byung Ha
authors.initials: BH
authors.lastname: Jeon
authors.forename: Yoo Joung
authors.initials: YJ
authors.lastname: Oh
authors.forename: Jae J
authors.initials: JJ
authors.lastname: Kim
authors.forename: Jong Chul
authors.initials: JC
authors.lastname: Rhee
authors.forename: Pum Soo
authors.initials: PS
authors.lastname: Kim
authors.forename: Mi Sook
authors.initials: MS
authors.lastname: Choi
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D001706:Biopsy; D002648:Child; D004269:DNA, Bacterial / Q000032:analysis / Q000302:isolation & purification; D005756:Gastritis / Q000382:microbiology; D005798:Genes, Bacterial; D005838:Genotype; D016481:Helicobacter Infections / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D007723:Korea; D008875:Middle Aged; D008969:Molecular Sequence Data; D010437:Peptic Ulcer / Q000382:microbiology; D021382:Protein Sorting Signals / Q000235:genetics*; D013274:Stomach Neoplasms / Q000382:microbiology
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D021382:Protein Sorting Signals; C074689:VacA protein, Helicobacter pylori