Bart J M, Knapp J, Gottstein B, El-Garch F, Giraudoux P, Glowatzki M L, Berthoud H, Maillard S, Piarroux R
Parasitology Department, SERF Team (Equipe Santé Environnement Rural Franche-Comté), Faculty of Medicine, University of Franche-Comté, France.
Infect Genet Evol. 2006 Sep;6(5):390-400. doi: 10.1016/j.meegid.2006.01.006. Epub 2006 Feb 28.
In order to explore the genetic diversity within Echinococcus multilocularis (E. multilocularis), the cestode responsible for the alveolar echinococcosis (AE) in humans, a microsatellite, composed of (CA) and (GA) repeats and designated EmsB, was isolated and characterized in view of its nature and potential field application. PCR-amplification with specific primers exhibited a high degree of size polymorphism between E. multilocularis and Echinococcus granulosus sheep (G1) and camel (G6) strains. Fluorescent-PCR was subsequently performed on a panel of E. multilocularis isolates to assess intra-species polymorphism level. EmsB provided a multi-peak profile, characterized by tandemly repeated microsatellite sequences in the E. multilocularis genome. This "repetition of repeats" feature provided to EmsB a high discriminatory power in that eight clusters, supported by bootstrap p-values larger than 95%, could be defined among the tested E. multilocularis samples. We were able to differentiate not only the Alaskan from the European samples, but also to detect different European isolate clusters. In total, 25 genotypes were defined within 37 E. multilocularis samples. Despite its complexity, this tandem repeated multi-loci microsatellite possesses the three important features for a molecular marker, i.e. sensitivity, repetitiveness and discriminatory power. It will permit assessing the genetic polymorphism of E. multilocularis and to investigate its spatial distribution in detail.
为了探究多房棘球绦虫（E. multilocularis）的遗传多样性，该绦虫是人类泡型包虫病（AE）的病原体，分离出一个由（CA）和（GA）重复序列组成的微卫星，并根据其性质和潜在的实际应用对其进行了表征，该微卫星被命名为EmsB。用特异性引物进行的PCR扩增显示，多房棘球绦虫与细粒棘球绦虫绵羊（G1）株和骆驼（G6）株之间存在高度的大小多态性。随后对一组多房棘球绦虫分离株进行了荧光PCR，以评估种内多态性水平。EmsB呈现出多峰图谱，其特征是多房棘球绦虫基因组中存在串联重复的微卫星序列。这种“重复的重复”特征赋予EmsB很高的鉴别力，因为在测试的多房棘球绦虫样本中可以定义出八个聚类，其自展p值大于95%。我们不仅能够区分阿拉斯加样本和欧洲样本，还能检测到不同的欧洲分离株聚类。在37个多房棘球绦虫样本中总共定义了25种基因型。尽管其结构复杂，但这种串联重复的多位点微卫星具有分子标记的三个重要特征，即敏感性、重复性和鉴别力。它将有助于评估多房棘球绦虫的遗传多态性，并详细研究其空间分布。
