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Prevalence of Vacuolating Cytotoxin Production and Distribution of Distinct vacA Alleles in Helicobacter pylori from China

1998; Oxford University Press; Volume: 178; Issue: 1 Linguagem: Inglês

10.1086/515601

1537-6613

Zijian Pan, Douglas E. Berg, René W. van der Hulst, Wan Wen Su, Aušra Raudonikiene, S D Xiao, J. Dankert, G N Tytgat, Arie van der Ende,

Veterinary medicine and infectious diseases

Studies of Helicobacter pylori from the West have linked production of vacuolating cytotoxin and a particular signal sequence (s1a) allele of the underlying vacA gene to peptic ulcer disease (PUD). Among Chinese H. pylori, most isolates from both PUD and gastritis patients were toxigenic (35/46 and 29/35, respectively). Polymerase chain reaction and DNA sequencing showed that 95 of 96 isolates carried vacA s1a alleles. In the mid-region, 78 of 96 isolates carried m2; 14 were m1-like but only 87% identical (DNA-level) to classical m1 and were designated m1b; the other 4 were unusual hybrids (m1b-type proximal, m2-type distal). Isolates with m1b and m1b-m2 alleles produced higher levels of vacuolating activity than did isolates with m2 alleles (P < .01). There was no association between any vacA allele and disease. These results suggest that the composition of H. pylori gene pools varies geographically and that other as-yet-unknown polymorphic H. pylori genes are important in PUD.