Despres L, Imbert-Establet D, Combes C, Bonhomme F
URA CNRS 1493, Laboratoire Génome et Populations, Université Montpellier II, France.
Mol Phylogenet Evol. 1992 Dec;1(4):295-304. doi: 10.1016/1055-7903(92)90005-2.
Molecular phylogenies for seven species of schistosomes, including four species infecting man, were constructed from PCR-amplified sequences of two ribosomal genes: one nuclear (internal transcribed spacer 2 in the ribosomal multigenic family) and one mitochondrial (16S rDNA). The two phylogenies obtained are congruent, and the data suggest that the mitochondrial sequence evolves about three times faster than the nuclear sequence. We propose a calibration of the phylogenetic tree of schistosomes that dates "human capture" of these parasites from other animal hosts (rodents and ruminants) in Africa to 1-10 million years ago, when the first hominids invaded savanna areas, which are the favorable environment for parasite transmission.
构建了七种血吸虫的分子系统发育树，其中包括四种感染人类的血吸虫，该系统发育树是基于两个核糖体基因的PCR扩增序列构建的：一个是核基因（核糖体多基因家族中的内转录间隔区2），另一个是线粒体基因（16S rDNA）。得到的两个系统发育树是一致的，数据表明线粒体序列的进化速度比核序列快约三倍。我们提出了一种血吸虫系统发育树的校准方法，该方法将这些寄生虫从非洲其他动物宿主（啮齿动物和反刍动物）“转移至人类宿主”的时间追溯到100万至1000万年前，当时第一批原始人类侵入了热带稀树草原地区，而该地区是寄生虫传播的有利环境。
