Helicobacter pylori vacA s1a and s1b alleles from clinical isolates from different regions of Chile show a distinct geographic distribution  

作　　者：MI Díaz A Valdivia P Martínez JL Palacios P Harris J Novales E Garrido D Valderrama C Shilling A Kirberg E Hebel J Fierro R Bravo F Siegel G Leon G Klapp A Venegas 

机构地区：[1]Departamento de Genética Molecular y Microbiología. Pontificia Universidad Católica de Chile. Santiago [2]Departamento de Pediatría [3]Centro de Diagnóstico Terapéutico Los Angeles [4]Unidad de Gastroenterología [5]Anatomía Patológica [6]Centro de Endoscopía Quirúrgica [7]Hospital Base de Linares [8]Hospital Regional de Valdivia [9]Instituto de Bioquímica [10]Hospital Regional de Punta Arenas

出　　处：《World Journal of Gastroenterology》2005年第40期6366-6372,共7页世界胃肠病学杂志（英文版）

基　　金：Supported by FONDECYT, Comision Nacional Cientifica y Tecnologica, Chile No.1000730 No.1030894 and No. 1000734 from and NIH No.DK54495

摘　　要：AIM： To establish the most common vacA alleles in Helicobacter pylori （ H pylon） strains isolated from Chilean patients and its relationship with gastritis and gastroduodenal ulcers, METHODS： Two hundred and forty five Hpyloriclinical isolates were obtained from 79 biopsies from Chilean infected patients suffedng from gastrointestinal diseases. An average of 2-3 strains per patient was isolated and the vac4 genotype was analyzed by PCR and 3% agarose electrophoresis. Some genotypes were checked by DNA sequencing. RESULTS： The most prevalent vacA genotype in Chilean patients was slb ml （76%）, followed by sla ml （21%）. In oontrast, the s2 m2 genotype was scarcely represented （3%）. The slb ml genotype was found most frequently linked to gastropathies （P〈0.05） rather than ulcers. Ulcers were found more commonly in male and older patients. Curiously, patents IMng in dties located North and far South of Santiago, thecapital and largest Chilean city, carried almost exclusively strains with the slb ml genotype. In contrast, patients from Santiago and cities located South of Santiago carded strains with either one or both sla ml and slb ml genotypes. Regarding the s2 m2 genotype, comparison with GenBank sequences revealed that Chilean s2 sequence was identical to those of Australian, American, and Colombian strains but quite different from those of Alaska and India. CONCLUSION： Differences in geographic distribution of the s and m vacA alleles in Chile and a relationship of slb ml genotype with gastritis were found. Sequence data in part support a hispanic origin for the vacA genotype. Asymmetric distribution of genotypes slb ml and s2 m2 recedes H Pyloristrain distribution in Spain and Portugal.AIM: To establish the most common vacA alleles in Helicobacter pylori(H pylori) strains isolated from Chilean patients and its relationship with gastritis and gastroduodenal ulcers.METHODS: Two hundred and forty five H pylori clinical isolates were obtained from 79 biopsies from Chilean infected patients suffering from gastrointestinal diseases. An average of 2-3 strains per patient was isolated and the vacA genotype was analyzed by PCR and 3% agarose electrophoresis. Some genotypes were checked by DNA sequencing.RESULTS: The most prevalent vacA genotype inChilean patients was s1b m1 (76%), followed by s1a m1 (21%). In contrast, the s2 m2 genotype was scarcely represented (3%).The s1b m1 genotype was found most frequently linked to gastropathies (P＜0.05) rather than ulcers. Ulcers were found more commonly in male and older patients. Curiously, patients living in cities located North and far South of Santiago, the capital and largest Chilean city, carried almost exclusively strains with the s1b m1 genotype. In contrast, patients from Santiago and cities located South of Santiago carried strains with either one or both s1a m1 and s1b m1 genotypes.Regarding the s2 m2 genotype, comparison with GenBank sequences revealed that Chilean s2 sequence was identical to those of Australian, American, and Colombian strains but quite different from those of Alaska and India.CONCLUSION: Differences in geographic distribution of the s and m vaccA alleles in Chile and a relationship of s1b m1 genotype with gastritis were found. Sequence data in part support a hispanic origin for the vacA genotype.Asymmetric distribution of genotypes s1b m1 and s2 m2recedes H Pyloristrain distribution in Spain and Portugal.

关 键 词：Hpylori vacA alleles Chilean isolates s1 s2 m1 and m2 sequences 

分 类 号：R573[医药卫生—消化系统]