Department of Microbiology, Faculty of Medicine Siriraj Hospital, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Prannok Road, Siriraj Hospital Siriraj Bangkoknoi, Bangkok 10700, Thailand.
Infect Genet Evol. 2011 Jul;11(5):1142-9. doi: 10.1016/j.meegid.2011.04.007. Epub 2011 Apr 14.
The Beijing family of Mycobacterium tuberculosis (MTB) has been shown to be highly virulent and is associated with tuberculosis outbreaks and drug resistance. To explore the evolutionary pathway of this genotype, 165 epidemiologically unlinked Beijing MTB isolates from Thailand were characterized based on IS6110, variable number of tandem repeats (VNTRs), region of differences (RDs) and single nucleotide polymorphisms (SNPs). Analysis based on VNTRs showed that 7 VNTRs were phylogenetically informative loci. Three of the seven VNTRs, 4156, 1982 and 1955, were promising markers for defining ancestral and modern Beijing sublineages. The evolutionary history of Beijing sublineages based on VNTR profiles showed dynamic changes in the repeat number, which also correlated with specific SNP STs. We constructed a refined, comprehensive phylogenetic tree based on multiple genetic markers from the Beijing strains from Thailand and combined the data with previous studies that were performed in South Africa and Japan. The phylogenetic tree showed how the modern Beijing and W-Beijing strains evolved from ancestral Beijing strains. The points at which the RD150 deletion occurred repeatedly were also demonstrated. The evolutionary scheme showed that most events were concordant with the SNP STs. Nevertheless, some SNPs used for sub-typing the Beijing family of MTB may not be irreversible, unique events.
北京家族分枝杆菌（MTB）已被证明具有高度的毒力，与结核病的爆发和耐药性有关。为了探索这种基因型的进化途径，对来自泰国的 165 株具有流行病学相关性的北京 MTB 分离株进行了 IS6110、可变数目串联重复序列（VNTRs）、区域差异（RDs）和单核苷酸多态性（SNPs）的特征分析。VNTR 分析表明，7 个 VNTR 是具有系统发育信息的位点。7 个 VNTR 中有 3 个，即 4156、1982 和 1955，是定义古老和现代北京亚系的有前途的标记。基于 VNTR 谱的北京亚系进化史显示重复数发生了动态变化，这也与特定的 SNP ST 相关。我们根据来自泰国的北京株的多个遗传标记构建了一个精细的、综合的系统发育树，并将数据与南非和日本的以前的研究结果进行了组合。该系统发育树展示了现代北京和 W-北京株系是如何从古老的北京株系进化而来的。还展示了 RD150 缺失重复发生的位置。进化方案表明，大多数事件与 SNP ST 是一致的。然而，用于分枝杆菌北京家族分型的一些 SNP 可能不是不可逆转的、独特的事件。
