Genotypes of the <i>Helicobacter pylori vacA</i> Signal Sequence Differ with Age in Korea

Original Article

The Korean Journal of Helicobacter and Upper Gastrointestinal Research 2004;4(1):15-20.
Published online June 30, 2004.

Genotypes of the Helicobacter pylori vacA Signal Sequence Differ with Age in Korea

연령 증가에 따른 Helicobacter pylori vacA 신호서열(Signal Sequence) 유전자형에 관한 연구

고재연·김유진·박화영·최연호· 전병하·오유정·이준행*·김재준*· 김범수^†·최미숙^‡

성균관대학교 의과대학 소아과학교실, 내과학교실*, 인하대학교 의과대학 내과학교실^†, 임상연구센터^‡

Abstract

Background/Aims: Studies on H. pylori genotypes have focused on adults in developed countries, and data on the genotypes of H. pylori recovered from the children are rare. To analyze the vacA genotypes of H. pylori from all age groups using new primers, which were designed for Korean strains. 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=0.002). The prevalence of s1a was 45.2% in patients ＜20 years old , but 14.9% in patients ≥50 years old. On the other hand, the prevalence of s1c or recombinant s1a-s1c was higher in those ≥50 years old. The distribution of the m-region did not differ significantly with age (p=0.110). Conclusions: Strain populations infecting Korean adults and children differ. (Korean J Helicobacter Upper Gastrointest Res 2004;4:15-20)

Key Words: Helicobacter pylori, Genotype, vacA, Signal sequence, Age