cagA and vacA in strains of Helicobacter pylori from ulcer and non-ulcerative dyspepsia patients

Abstract

Background: The cytotoxin associated gene A (cagA), and the vacuolating cytotoxin gene A (vacA) of Helicobacter pylori have been associated to phenotypic characteristics of virulence. The objectives of this study were to detect the presence of cagA and to characterize the allelic variants of vacA in 63 strains of H. pylori isolated from colonized individuals with different clinical outcomes. Methods: 38 strains were isolated from patients with non-ulcerative dyspepsia (NUD) and 25 were isolated from colonized individuals with peptic ulcers. The genotypic characterization was carried out utilizing PCR methodology. The presence of the cagA gene was detected using two set of primers from the middle conservative region of the cagA, and primers for the signal and middle region were used for the genotyping of vacA Results: The presence of cagA showed similar rates in strains from peptic ulcers (60%) and NUD patients (55%). Also similar was the prevalence of the allelic form s1 of vacA betwee