Population structure and genetic typing of Trypanosoma cruzi, the agent of Chagas disease:: a multilocus enzyme electrophoresis approach
Population structure and genetic typing of Trypanosoma cruzi, the agent of Chagas disease:: a multilocus enzyme electrophoresis approach
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DOI：
10.1017/s0031182099005661
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发表时间：
2000-05-01
期刊：
影响因子：
2.4
通讯作者：
Tibayrenc, M
中科院分区：
文献类型：
--
作者：
Barnabé, C;Brisse, S;Tibayrenc, M
采用多位点酶电泳法对来自广泛生态地理范围的434个克氏锥虫种群的22个遗传位点进行了分析。观察到强烈的连锁不平衡，与地理距离无关，2个主要遗传集群各有很大的异质性。这些结果支持了以前的假设，即克氏体自然种群由高度多样化的遗传克隆组成，分布在2个主要的系统发育谱系中：谱系1在流行地区最普遍，在森林循环中更常见，而谱系2在调查地区的南部主要存在于人类和家养循环中，进一步划分为5个较小的遗传亚区。因此，T. cruzi似乎被细分为至少6个“离散类型单位”或dtu （Tibayrenc, 1998a-c）。我们已经确定了各种特定的同工酶标记（“标签”；Tibayrenc，同前文献），适用于这些dtu的常规鉴定，用于流行病学跟踪目的。我们讨论了与以前分类的对应关系，以及最近发现恰加斯病90周年研讨会的建议，以及克氏锥虫遗传变异性对这种寄生虫生物医学多样性的影响。
A set of 434 Trypanosoma cruzi stocks from a wide ecogeographical range was analysed by Multilocus Enzyme Electrophoresis for 22 genetic loci. Strong linkage disequilibrium, not associated with geographical distance, and 2 main genetic clusters each considerably heterogeneous, was observed. These results support the hypotheses previously proposed that T. cruzi natural populations are composed of highly diversified genetic clones distributed into 2 main phylogenetic lineages: lineage 1, the most ubiquitous in the endemic area, was more frequently observed in sylvatic cycles, whereas lineage 2, predominant in humans and domestic cycles, in the southern part of the area surveyed, was further partitioned into 5 lesser genetic subdivisions. T. cruzi appears therefore subdivided into at least 6 'discrete typing units' or DTUs (Tibayrenc, 1998a-c). We have identified various specific isoenzyme markers ('tags'; Tibayrenc, op. cit.) suitable for the routine identification of these DTUs for epidemiological tracking purposes. We discuss the correspondence with previous classifications and with the recent recommendations of the 90th anniversary of the discovery of Chagas disease symposium, as well as the impact of T. cruzi genetic variability on this parasite's biomedical diversity.