Genotyping of Helicobacter pylori strains isolated from patients with NUD, DU, GU and GC by RAPD-PCR

Helicobacter pylori is a genetically diverse gastric pathogen that chronically infects billions of people worldwide, typically beginning in infancy and lasting for decades. It is a major cause of peptic ulcers and it is an early risk factor for gastric cancer which is the most frequently lethal malignancy globally. This project was designed to genotype H. pylori isolates isolated from patients with NUD, DU, GU and GC by the polymerase chain reaction [PCR]-based on Randomly Amplified Polymorphic DNA [RAPD] fingerprinting technique. Eighty patients admitted to the gastroenterology unit at Sharyati hospital in Iran were included in this study. Gastric biopsy specimens were inoculated onto selective medium then were cultured for 3 to 5 days at 37 °C under microaerobic conditions. Genomic DNA was extracted using a commercially available Qiagen kit. RAPD-PCR was used to genotype isolates. Six different RAPD patterns [A-F] were seen in more than one isolate which were as follow; pattern A: 9 [16.98%], B: 6 [11.33%], C: 5 [9.43%], D: 3 [5.66%], E: 2 [3.77%] and F: 2 [3.77%]. Twenty six [49.06%] of 53 isolates showed a unique RAPD pattern that were not similar to each other. A significant relationship was not seen between a single RAPD pattern and a gastric disorder [P>0.05]. The results of this study suggest a high level of DNA sequence diversity among H. pylori isolates and it is better to use sequencing method for surveying of Helicobacter pylori genome rather than RAPD-PCR