Analysis of the vacA, cagA, cagE, iceA, and babA2 genes in Helicobacter pylori from sixty-one pediatric patients from the Midwestern United States.

This study was designed to characterize H. pylori from pediatric gastric biopsy specimens in terms of several genes (vacA, cagA, cagE, iceA1, iceA2, and babA2) proposed to be involved in the pathogenesis of this organism. Many of these genes have been studied in adult H. pylori isolates, however, these genes have not been well characterized in H. pylori from children. Using PCR we observed that 44% of the H. pylori in our biopsies shared two common genotypes (vacA s1b m1, cagA, cagE, iceA2 +/- babA2). While 26% of the H. pylori had unique genotypes. The cag pathogenicity island associated genes, cagA and cagE, were found together in 64% or our H. pylori, while 84% were iceA2 positive. The presence of the babA2 gene has been proposed to be associated with a higher risk of H. pylori related diseases, however, we found that only 36% of our H. pylori contained this gene.