OBJECTIVETo compare the prevalence of Helicobacter pylori (Hp) infection in children of Zhuang and Mulan ethnic groups, Guangxi Luocheng county, China and in children of Jing ethnic group, Central Vietnam and to analyze the association of HLA-DQA1 alleles of these ethnic groups' children with Hp infection.

METHODSSerodiagnosis by determining Hp antibody with ELISA and determination of serum CagA, VacA and urease antibodies by immunoblotting were performed for 54 Zhuang, 76 Mulan and 109 Jing children. Polymerase chain reaction-single strand polymorphism (PCR-SSP) technique was applied to determine the polymorphism of the HLA-DQA1 locus of these children and then the association of HLA-DQA1 alleles of these minority children with Hp infection was analyzed by SAS software.

RESULTSThe prevalence of Hp infection were 39% in Vietnamese Jing nationality, which was significantly lower than that in children of Guangxi Luocheng county (65% in Zhuang nationality and 58% in Mulan nationality) (P < 0.01). The distribution of HLA-DQA1 locus was not significantly different among the 3 groups. The frequency of HLA-DQA1 * 0104 allele was significantly higher in children with Hp infection than in children without Hp infection in each of the 3 groups (P < 0.01).

CONCLUSIONThe results indicated that the prevalence of Hp infection in Zhuang and Mulan minority ethnic groups in Guangxi, China was higher than that in Vietnamese Jing ethnic group children. HLA-DQA1 * 0104 allele may be associated with susceptibility to Hp infection.