中文摘要：

目的评价多位点MLVA的15位点组合在北京基因型结核分枝杆菌（MTB）基因分型研究中的应用价值。方法采用MLVA（15位点）对来源于北京胸科医院的72株北京基因型MTB菌株进行基因分型，并将结果与金标准IS6110-RFLP的分型结果进行比较。结果MLVA（15位点）分型后共得到59个类型，其中53个为独特类型，其总体分辨力为0．990，多态性较好的位点有Qub—J1b、Mtub21和QUB-26；IS6110-RFLP分型后共得到69个类型，其中66个为独特类型，分辨力高达0．999，并可对MLVA（15位点）中成簇的菌株进一步区分。结论MLVA（15位点）在北京基因型菌株中具有较好的分辨能力，但成簇菌株仍需采用金标准IS6110-RFLP进一步细分。

英文摘要：

Objective To evaluate the application of multiple locus variable number tandem repeat analysis （MLVA, 15-locus set）for genotyping of Mycobacterium tuberculosis （MTB） strains of Beijing genotype. Methods Total 72 Beijing genotype MTB strains obtained from Beijing Thoracic Hospital were genotyped by MLVA （15-locus set）. The results were compared with that generated from ＂gold standard＂ IS6110-RFLP. Results After genotyped by MLVA （ 15-locus set）, 72 strains were grouped into 59 types, of which 53 were unique types. The Hunter-Gaston index （HGI） of MLVA （ 15-locus set） was 0. 990. The loci QUB-11b, Mtub 21 and QUB-26 were polymorphic in selected Beijing genotype strains. Genotyping by IS6110-RFLP generated 69 types, of which 66 were unique types. The HGI of IS6110-RFLP was up to 0. 999, and the MLVA （ 15-locus set） clustered strains could be further subdivided. Conclusion MLVA （ 15-locus set） showed better discriminatory ability in Beijing genotype MTB strains, though secondary typing of clustered strains by IS6110-RFLP is needed.