Genotypes of the Helicobacter pylori vacA signal sequence differ with age in Korea

Helicobacter. 2004 Feb;9(1):54-8. doi: 10.1111/j.1083-4389.2004.00198.x.

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.

Materials and 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.

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aging*
  • Amino Acid Sequence
  • Bacterial Proteins / genetics*
  • Base Sequence
  • Biopsy
  • Child
  • DNA, Bacterial / analysis
  • DNA, Bacterial / isolation & purification
  • Gastritis / microbiology
  • Genes, Bacterial
  • Genotype
  • Helicobacter Infections / microbiology*
  • Helicobacter pylori / genetics*
  • Helicobacter pylori / isolation & purification
  • Humans
  • Korea
  • Middle Aged
  • Molecular Sequence Data
  • Peptic Ulcer / microbiology
  • Protein Sorting Signals / genetics*
  • Stomach Neoplasms / microbiology

Substances

  • Bacterial Proteins
  • DNA, Bacterial
  • Protein Sorting Signals
  • VacA protein, Helicobacter pylori