RESUMO
Various tyrosine phosphorylation motif regions of H. pylori cagA exist. The number of these regions was found to have some influence on cell signaling, which was found to be more pronounced when in D (ESS) region than in C (WSS) region. A molecular biological method with multiplex PCR was developed to distinguish C and D regions, and to identify the repetition number of tyrosine phosphorylation of the cagA gene. Multiplex PCR using novel primer sets was performed on 73 strains of H. pylori isolated from Korean patients with upper gastrointestinal diseases. The Western cagA was identified in only 3 strains (4.1%) whereas East Asia cagA was identified in 69 strains (94.5%). These results were reconfirmed through a sequencing analysis. The method developed in this study would be useful for monitoring the repeated number of C and D regions of tyrosine phosphorylation motifs in H. pylori cagA.