Gutierrez M Cristina, Ahmed Niyaz, Willery Eve, Narayanan Sujatha, Hasnain Seyed E, Chauhan Devendra S, Katoch Vishwa M, Vincent Véronique, Locht Camille, Supply Philip
Institut Pasteur, Paris, France.
Emerg Infect Dis. 2006 Sep;12(9):1367-74. doi: 10.3201/eid1209.050017.
Although India has the highest prevalence of tuberculosis (TB) worldwide, the genetic diversity of Mycobacterium tuberculosis in India is largely unknown. A collection of 91 isolates originating from 12 different regions spread across the country were analyzed by genotyping using 21 loci with variable-number tandem repeats (VNTRs), by spoligotyping, by principal genetic grouping (PGG), and by deletion analysis of M. tuberculosis-specific deletion region 1. The isolates showed highly diverse VNTR genotypes. Nevertheless, highly congruent groupings identified by using the 4 independent sets of markers permitted a clear definition of 3 prevalent PGG1 lineages, which corresponded to the "ancestral" East African-Indian, the Delhi, and the Beijing/W genogroups. A few isolates from PGG2 lineages and a single representative of the presumably most recent PGG3 were identified. These observations suggest a predominance of ancestral M. tuberculosis genotypes in the Indian subcontinent, which supports the hypothesis that India is an ancient endemic focus of TB.
尽管印度是全球结核病（TB）患病率最高的国家，但印度结核分枝杆菌的基因多样性在很大程度上仍不为人知。我们对来自印度全国12个不同地区的91株分离菌进行了分析，采用21个具有可变数目串联重复序列（VNTR）的位点进行基因分型、间隔寡核苷酸分型、主要基因分组（PGG）以及结核分枝杆菌特异性缺失区域1的缺失分析。这些分离菌显示出高度多样的VNTR基因型。然而，通过使用4组独立的标记物所确定的高度一致的分组，使得能够清晰地定义3种常见的PGG1谱系，它们分别对应于“祖先型”东非-印度、德里以及北京/W基因群。还鉴定出了一些来自PGG2谱系的分离菌以及大概是最新的PGG3的单一代表菌株。这些观察结果表明，在印度次大陆，祖先型结核分枝杆菌基因型占主导地位，这支持了印度是结核病古老流行病灶的假说。
