Tibayrenc M
Centre d'Etudes sur le Polymorphisme des Microorganismes, UMR CNRS/ORSTOM 9926, Montpellier, France.
Int J Parasitol. 1998 Jan;28(1):85-104. doi: 10.1016/s0020-7519(97)00180-x.
This paper emphasises the relevance of the concepts and methods of evolutionary genetics for studying the epidemiology of parasitic protozoa and other pathogenic agents. Population genetics and phylogenetic analysis both contribute to identifying the relevant evolutionary and epidemiologically discrete units of research (Discrete typing units = DTUs), that can be equated to distinct phylogenetic lines. It is necessary (i) to establish that a given species represents a reliable DTU; (ii) to see whether a given species is further structured into lower DTUs that correspond to either clonal lineages or to cryptic species, and could exhibit distinct biomedical properties (virulence, resistance to drugs, etc). DTUs at the species and subspecies level can be conveniently identified by specific genetic markers or sets of genetic markers ("tags") for epidemiological follow-up. For any kind of pathogen (protozoa, fungi, bacteria, viruses), DTUs represent the relevant units of research, not only for epidemiology, but also, for other applied researches (clinical study, pathogenicity, vaccine and drug design, immunology, etc). The development of an "integrated genetic epidemiology of infectious diseases", that would explore the respective role of, and the interactions between, the genetic diversity (and its biological consequences) of the pathogen, the host and the vector (in the case of vector-borne diseases) is called for.
本文强调了进化遗传学的概念和方法对于研究寄生原生动物及其他病原体流行病学的相关性。群体遗传学和系统发育分析都有助于识别相关的进化和流行病学离散研究单位（离散分型单位=DTUs），这些单位可等同于不同的系统发育谱系。有必要：（i）确定某个特定物种代表一个可靠的DTU；（ii）查看某个特定物种是否进一步细分为对应于克隆谱系或隐性物种的更低级DTUs，并且可能表现出不同的生物医学特性（毒力、耐药性等）。物种和亚种水平的DTUs可以通过特定的遗传标记或遗传标记集（“标签”）方便地识别，用于流行病学跟踪。对于任何类型的病原体（原生动物、真菌、细菌、病毒），DTUs不仅是流行病学研究的相关单位，也是其他应用研究（临床研究、致病性、疫苗和药物设计、免疫学等）的相关单位。我们需要发展一种“传染病综合遗传流行病学”，以探究病原体、宿主和媒介（在媒介传播疾病的情况下）的遗传多样性（及其生物学后果）各自的作用以及它们之间的相互作用。
