GENOTYPING OF HELICOBACTER PYLORI GRAM-NEGATIVE PATHOGEN STRAINS BY CAGA, VACA AND ICEA VIRULENCE GENES: A MOLECULAR EPIDEMIOLOGICAL STUDY IN A CENTRAL ASIAN POPULATION

Ibragimov Xamza Aminbayevich

Authors

Ibragimov Xamza Aminbayevich DSc in Biological Sciences, Professor Asia International University

Keywords:

Helicobacter pylori, cagA, vacA, iceA, genotyping, virulence genes, gastric cancer, peptic ulcer disease, Central Asia, Uzbekistan.

Abstract

Background: Helicobacter pylori is a gram-negative, microaerophilic spiral bacterium colonising the gastric mucosa of approximately half of the world's population. Virulence gene polymorphisms—particularly in cagA (cytotoxin-associated gene A), vacA (vacuolating cytotoxin A), and iceA (induced by contact with epithelium)—determine the risk of progression from asymptomatic colonisation to peptic ulcer disease, gastric atrophy, and gastric adenocarcinoma. The distribution of these genotypes varies substantially among geographic populations, yet no systematic genotyping study has been conducted in Uzbekistan or the broader Central Asian region.

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