Related Experiment Video
Updated: Jun 18, 2026
06:21
Multi-Gene Single Nucleotide Polymorphism Detection in Gastric Cancer Based on Ion Semiconductor Sequencing Platform
Published on: May 10, 2024
Epidemiological link between gastric disease and polymorphisms in VacA and CagA
Sungil Jang1, Kathleen R Jones, Cara H Olsen
1Department of Oral Biology, Oral Science Research Center, BK21 Project, Yonsei University College of Dentistry, Seoul, South Korea.
Journal of Clinical Microbiology
|December 4, 2009
Summary
Helicobacter pylori genotypes, specifically cagA and vacA alleles, are linked to the severity of gastric diseases in South Korea. Understanding these variations can help predict disease outcomes and inform public health strategies for H. pylori infections.
Area of Science:
- Microbiology
- Genetics
- Gastroenterology
Background:
- Helicobacter pylori infection is linked to various gastric diseases, including gastritis, peptic ulcer disease, and gastric cancer.
- The reasons why some individuals develop severe disease manifestations remain unclear.
- Genotypic variations in H. pylori may influence disease severity.
Purpose of the Study:
- To investigate the association between specific Helicobacter pylori genotypes (vacA and cagA alleles) and disease severity in a South Korean population.
- To determine if these genotypic variations correlate with disease state, sex, or cagA allele type.
Main Methods:
- Genotyping of 225 South Korean H. pylori strains for vacA alleles (s1/i1/m1, s1/i1/m2, s1/i2/m2).
- Analysis of cagA allele types.
- Statistical analysis using Fisher's exact test and log linear modeling to assess associations between genotypes, sex, and disease outcome.
Main Results:
- A significant association was found between variations in cagA and vacA alleles (P = 0.0007).
- These variations were shown to affect the severity of disease outcome (P = 0.027).
- Variation in the middle region of VacA significantly influenced vacA allele distribution across gender (P = 0.008) and disease outcome (P = 0.011).
Conclusions:
- The majority of H. pylori strains in this South Korean population carry the vacA s1/i1/m1 allele and the CagA EPIYA-ABD allele.
- These prevalent genotypes may contribute to the high incidence of gastric diseases, including gastric cancer, in this region.
- Genotypic analysis of H. pylori provides insights into disease pathogenesis and potential risk stratification.
Related Concept Videos
01:26Gastritis II: Pathophysiology
The pathophysiology of gastritis begins with the colonization of the stomach lining by Helicobacter pylori (H. pylori). This bacterium spreads mainly via the oral-oral route through saliva or shared utensils, and can also be transmitted in overcrowded or unhygienic environments through contaminated water, despite its brief survival outside the body.ColonizationOnce ingested, H. pylori enters the stomach and begins colonization by navigating through the mucus layer lining the stomach wall. It...
01:50What is Monogastric Digestion?
The human body contains a monogastric digestive system. In a monogastric digestive system, the stomach only contains one chamber in which it digests food. Several other animal species also have monogastric digestive systems, including pigs, horses, dogs, and birds. This chapter, however, focuses on the human digestive system.
01:05Single Nucleotide Polymorphisms-SNPs
A single nucleotide polymorphism or SNP is a single nucleotide variation at a specific genomic position in a large population. It is the most prevalent type of sequence variation found in the human genome. Point mutations that occur in more than 1% of the population qualify as SNPs. These are present once every 1000 nucleotides on an average in the human genome. Replacement of a purine with another purine (A/G) or a pyrimidine with another pyrimidine (C/T) is known as a transition. In contrast,...
01:17Gastritis-II: Pathophysiology
Gastritis is marked by disruption of the mucosal barrier that usually protects the stomach tissue from digestive juices and manifests in acute and chronic forms.
In acute gastritis, the gastric mucosa becomes swollen and red and undergoes superficial erosion. Superficial ulceration may lead to bleeding.
In chronic gastritis, persistent or repeated insults lead to chronic inflammatory changes and, eventually, thinning or atrophy of the gastric tissue.
Gastritis can stem from various causes, each...
In acute gastritis, the gastric mucosa becomes swollen and red and undergoes superficial erosion. Superficial ulceration may lead to bleeding.
In chronic gastritis, persistent or repeated insults lead to chronic inflammatory changes and, eventually, thinning or atrophy of the gastric tissue.
Gastritis can stem from various causes, each...
01:27Peptic Ulcer
Peptic ulcers are erosive lesions of the gastric or duodenal lining, most commonly caused by Helicobacter pylori infection. This Gram-negative, helical bacterium has adapted to survive the stomach’s acidic environment by producing urease, which converts urea into ammonia and carbon dioxide. The ammonia neutralizes gastric acid in the bacterium’s immediate environment, allowing colonization of the gastric mucosa. H. pylori attaches to mucus-secreting epithelial cells, penetrates the mucus...
01:29Pharmacogenomics: Identification of New Drug Targets
Advances in genomics have profoundly influenced drug discovery by increasing both the speed and accuracy of pharmaceutical development. Pharmacogenomics, which examines how genetic variation influences drug response, facilitates the identification of novel therapeutic targets and enables patient stratification for personalized treatment. These strategies contribute to improved drug efficacy, minimized adverse effects, and more efficient clinical trial design.Mapping genetic differences...