Laboratory for Mycobacteria, University Clinic of Respiratory and Allergic Diseases Colnik, Colnik, Slovenia.
Respir Med. 2011 Oct;105 Suppl 1:S67-73. doi: 10.1016/S0954-6111(11)70014-2.
Slovenia is one of the few countries where IS6110 RFLP is applied for genotyping M. tuberculosis at a nationwide level, which has been in effect since 2000. Based on S6110 RFLP clustering, typical risk factors and routes of M. tuberculosis transmission were identified, such as alcohol abuse, homelessness, and bars. However, IS6110 RFLP typing suffers from important limitations including a long wait for results, which reduces the potential benefit of molecular-guided tuberculosis (TB) control. PCR-based 24-locus MIRU-VNTR typing combined with spoligotyping has recently emerged as a potential alternative for faster, large-scale genotyping of M. tuberculosis.
We compared these genotyping methods for analyzing 196 Slovenian Mycobacterium tuberculosis isolates representing 97.5% of all culture-positive cases included in the Slovenian TB Registry in 2008.
IS6110 RFLP and 24-locus MIRU-VNTR typing combined with spoligotyping identified 157 and 155 distinct profiles, 135 and 125 unique isolates, and 61 and 71 clustered isolates grouped into 22 and 29 clusters, respectively. The discriminatory indexes were very close, at 0.9963 and 0.9965, respectively. The majority of the molecular clusters defined by either of the two methods were identical, including in the few cases for which epidemiological links were available. The differences frequently consisted of single-band changes in IS6170-RFLP profiles subdividing a MIRU-VNTR/spoligotype-based cluster.
Our one-year nationwide study showed that the results of 24-locus MIRU-VNTR typing combined with spoligotyping reached a high level of concordance with those obtained from IS6110 RFLP typing.
斯洛文尼亚是少数几个在全国范围内应用 IS6110 RFLP 对结核分枝杆菌进行基因分型的国家之一,该方法自 2000 年以来一直在使用。基于 IS6110 RFLP 聚类,可以确定结核分枝杆菌传播的典型危险因素和途径,例如酗酒、无家可归和酒吧。然而,IS6110 RFLP 分型存在重要局限性,包括等待结果的时间较长,这降低了分子指导结核病(TB)控制的潜在益处。基于 PCR 的 24 位基因 MIRU-VNTR 分型结合 spoligotyping 最近已成为快速、大规模结核分枝杆菌基因分型的潜在替代方法。
我们比较了这两种基因分型方法,分析了 196 株代表 2008 年斯洛文尼亚结核病登记处纳入的所有培养阳性病例的 97.5%的斯洛文尼亚结核分枝杆菌分离株。
IS6110 RFLP 和 24 位基因 MIRU-VNTR 分型结合 spoligotyping 鉴定出 157 个和 155 个不同的谱型,135 个和 125 个独特的分离株,61 个和 71 个聚类分离株分别分为 22 个和 29 个聚类。两个方法的区分指数非常接近,分别为 0.9963 和 0.9965。两种方法定义的大多数分子聚类都是相同的,包括在有流行病学联系的少数情况下。差异通常包括 IS6170-RFLP 谱型中单个带的变化,这些变化细分了基于 MIRU-VNTR/spoligotype 的聚类。
我们为期一年的全国性研究表明,24 位基因 MIRU-VNTR 分型结合 spoligotyping 的结果与 IS6110 RFLP 分型的结果高度一致。