Characterizing in Myanmar.

BACKGROUND/AIMS: Differences in the infection rate are not sufficient to clarify the dissimilarity of gastric cancer incidence between Myanmar and its neighboring countries. To better understand this trend, the virulence gene was characterized in Myanmar.

METHODS

Glutamate-proline-isoleucine-tyrosine-alanine (EPIYA) patterns and CagA multimerization (CM) motifs of genotypes were examined by performing polymerase chain reactions and DNA sequencing.

RESULTS

Of 69 tested strains, -positive patients had significantly more severe histological scores in their antrum than -negative patients. Sequence analysis revealed that 94.1% of strains had Western-type containing an EPIYA motif (92.6%) or EPIYT motif (6.4%). The intestinal metaplasia scores in the antral of patients infected with the ABC and ABCC types of were significantly higher than those of patients with AB-type . Interestingly, in patients infected with , 46.3% of strains with three EPIYA motifs contained two identical Western-typical CM motifs, and these patients showed significantly higher antrum inflammation scores than patients infected with two identical nontypical-CM motif strains (p=0.02).

CONCLUSIONS

In Myanmarese strains, Western-type was predominant. The presence of CM motifs and the proportion of multiple EPIYA-C segments might partially explain the intermediate gastric cancer risk found in Myanmar.