四川省结核分枝杆菌基因分型中MIRU-VNTR位点稳定性评价及保守位点分析

Analysis and evaluation of the stability and conservation of MIRU-VNTR loci of Mycobacterium tuberculosis in Sichuan

本文收集了四川省2009-2013年184株结核分枝杆菌菌株,用标准12 MIRUVNTR位点组对四川省结核分枝杆菌菌株进行基因分型研究,评估四川地区一线VNTR分型位点的稳定性,确定四川地区保守位点组合及主要MIT型.184株结核分枝杆菌基因分型后得到51个基因型,12个基因型成簇.本研究确定当前四川地区12高分辨力位点VNTR分型方法中的7个MIRU位点依然具有较高的分辩能力（h〉0.55）.MIRU02,MIRU20,MIRU23,MIRU24为多态性最低的4个位点（0≤h〈0.4）,保守位点组的主要MIT型为“2251”.四川省结核分枝杆菌VNTR位点的多态性保持稳定,目前采用的12高分辨力VNTR位点依然稳定可靠.

The standard 12-locus mycobacterial interspersed repetitive units-variable number tandem re- peats （MIRU-VNTR） was performed on 184 M. tuberculosis isolates which were randomly selected from the collection during 2009 to 2013 in Sichuan province to confirm the set of conservative loci and the predominant MIT of the set of poorest discriminative loci as well as to evaluate the stability of the set of the first-line typing loci using in this region. The study showed 184 M. tuberculosis isolates were divided into 51 genotypes and 12 clusters. We confirmed that the 7 MIRU loci which were included in the adjusted scheme of the 12 highly discriminatory VNTR loci were effective （h〉0. 55） and the 4 poorest discriminative loci were MIRU02, MIRU20, MIRU23, MIRU24 （0≤h〈0.4）. The MIT ＂2251＂ was predominant group that represented the groups by the set of 4 conservative loci. The frequency of MIRU- VNTR alleles and allelic diversity at each locus in M. tuberculosis isolates from Sichuan remained sta-ble, so the set of the first-line typing loci using at present was still effective.