新疆结核分枝杆菌临床分离株VNTR基因型的初步研究

Preliminary study on VNTR genotypes of Mycobacterium Tuberculosis clinical isolates from Xinjiang with MLVA method

目的研究新疆结核分枝杆菌可变数目串联重复序列(variable number tandemrepeats,VNTR)基因分型,初步了解其基因型多态性状况及主要流行株。方法在新疆维吾尔自治区胸科医院收集一个连续时间段的结核分枝杆菌临床分离菌株,采用多位点可变数目串联重复序列分析(the Multiple Loci VNTR Analysis,MLVA)方法进行基因分型研究。基因聚类分析采用BioNumerics5.0数据库软件。结果共收集到结核分枝杆菌临床分离菌株175株,运用MLVA175株菌可分为8个基因群(分别为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ、Ⅶ、Ⅷ)119种基因型,其中Ⅰ群所占比例最大,达69.14%,经与Spoligotyping结果综合分析,I群即是北京家族,Ⅱ群为CAS家族。结论新疆结核分枝杆菌临床菌株存在明显的VNTR基因多态性,主要流行菌株为VNTRⅠ群(北京基因型),首次发现新疆临床菌株中存在CAS家族。

In order to investigate the VNTR（variable number tandem repeats）genotypes of Mycobacterium tuberculosis（M.tuberculosis）clinical isolates in Xinjiang,and the gene polymorphism and main epidemic strain of M.tuberculosis in this area,M.tuberculosis clinical isolates were collected in the Chest Hospital of Xinjiang Uyghur Autonomous Region in certain period continuously,and the genotyping on these strains was studied with the Multiple Loci VNTR Analysis（MLVA）.Genotyping cluster was analysed with BioNumerics 5.0 software.Of 175 M.tuberculosis clinical isolates have been collected in this study.The spoligotype results showed that there were 8 clusters（Ⅰto Ⅷ）containing 119 genotypes,in which the biggest cluster is clusterⅠ,which was accounting for a proportion of 69.14%.Comparing with the results of another study with Spoligotyping,cluster I belonged to Beijing family and clusterⅡbelonged to CAS family.It is confirmed that there is VNTR gene polymorphism obviously in Xinjiang M.tuberculosis clinical strains,in which the main epidemic strain of M.tuberculosis is VNTR clusterⅠ（Beijing genotype）.It is the first time to find the CAS family in Xinjiang.