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。
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.