Genotyping of Helicobacter pylori strains isolated from biopsy samples in Shahrekord city using RAPD PCR method

Subject Areas : microbiology

hossein aghajani ¹ , Hossein Khodabandeh shahraki ²

1 - Department of Microbiology, Faculty of Basic Sciences, Islamic Azad University, Shahrekord Branch, Shahrekord, Iran.
2 -

Received: 2025-07-10 Accepted : 2025-07-11 Published : 2025-07-11

Keywords: Biopsy, Genotyping, Helicobacter pylori, RAPD-PCR.,

Abstract :

Helicobacter pylori is an important cause of gastrointestinal diseases. Since genetic diversity within the Helicobacter pylori population occurs in large quantities, methods such as RAPD-PCR were used to determine the possible relationship between specific Helicobacter pylori genotypes and various gastric diseases. In this study, the genetic pattern of Helicobacter pylori strains isolated from different patients with dyspepsia was investigated by RAPD-PCR.

During this study, biopsy samples from 40 patients, including 20 normal patients, 16 ulcer patients, and 4 cancer patients, were extracted using a DNA extraction kit manufactured by Cinagene Company, and the strains were identified in the presence of 16srRNA primers.

In this study, after performing the determined in the presence of specific primers and the strains were genotyping was performed by RAPD-PCR. PCR test for the definitive diagnosis of Helicobacter pylori, all samples were detected positive with a band of 109 base pairs. The vacA gene was detected in 30 samples (70%) and the cagA gene in 2 samples. In the dendrogram obtained in the RAPD-PCR test in 40 Helicobacter pylori strains examined in biopsy samples, a general affinity between 54 and 98% among the isolates is evident. All isolates were distinguished from each other in 9 main clusters. At a similarity coefficient of 80%, a total of 30 profiles including 9 clusters and 21 separate points were identified.

In the examination of electrophoretic DNA fragments, the following patterns were observed, indicating that the results obtained are genetically diverse and heterogeneous. The results obtained on 20 strains isolated from normal patients showed that each of the strains has its own genetic fingerprint pattern.

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