PDF(Pubmed)
Abstract：
Dibothriocephalus latus is the most frequent causative agent of fish-borne zoonosis (diphyllobothriosis) in Europe, where it is currently circulating mainly in the Alpine lakes region (ALR) and Russia. Three mitochondrial genes (cox1, cob and nad3) and 6 microsatellite loci were analysed to determine how is the recently detected triploidy/parthenogenesis in tapeworms from ALR displayed at the DNA level. A geographically distant population from the Krasnoyarsk Reservoir in Russia (RU-KR) was analysed as a comparative population. One or 2 alleles of each microsatellite locus was detected in plerocercoids from RU-KR, corresponding to the microsatellite pattern of a diploid organism. In contrast, 1–3 alleles were observed in tapeworms from ALR, in accordance with their triploidy. The high diversity of mitochondrial haplotypes in D. latus from RU-KR implied an original and relatively stable population, but the identical structure of mitochondrial genes of tapeworms from ALR was probably a consequence of a bottleneck typical of introduced populations. These results indicated that the diploid/sexually reproducing population from RU-KR was ancestral, located within the centre of the distribution of the species, and the triploid/parthenogenetically reproducing subalpine population was at the margin of the distribution. The current study revealed the allelic structure of the microsatellite loci in the triploid tapeworm for the first time.
摘要：
双头鱼是欧洲鱼类传播的人畜共患病（双叶病）的最常见病原体，目前主要在高山湖泊地区（ALR）和俄罗斯流通。分析了三个线粒体基因（cox1，cob和nad3）和6个微卫星基因座，以确定如何在DNA水平上显示最近检测到的来自ALR的the虫的三倍体/孤雌生殖。分析了与俄罗斯克拉斯诺亚尔斯克水库（RU-KR）相距遥远的人口作为比较人口。在RU-KR的plerocercoids中检测到每个微卫星基因座的一个或两个等位基因，对应于二倍体生物的微卫星模式。相比之下,在来自ALR的tape虫中观察到1-3个等位基因，根据他们的三倍体。RU-KR中D.latus线粒体单倍型的高度多样性暗示了原始且相对稳定的种群，但是来自ALR的tape虫的线粒体基因的相同结构可能是引入种群的典型瓶颈的结果。这些结果表明，RU-KR的二倍体/有性繁殖种群是祖先，位于物种分布的中心，三倍体/孤雌生殖亚高山种群处于分布边缘。当前的研究首次揭示了三倍体tape虫中微卫星基因座的等位基因结构。
