Babkin Igor V, Tikunov Artem Y, Gologljova Irina, Tikunova Nina V
1 Laboratory of Molecular Microbiology, Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentiev Avenue, Novosibirsk 630090, Russia.
2 Department of Virology, National Institute for Health Development, Hiiu 42, 11619 Tallinn, Estonia.
J Parasitol. 2018 Jun;104(3):337-341. doi: 10.1645/17-186. Epub 2018 Feb 27.
In southern regions of Western Siberia, Ixodes persulcatus ticks co-exist with Ixodes pavlovskyi. Both tick species have similar morphology, and natural hybridization of I. persulcatus and I. pavlovskyi ticks has been observed. To investigate the role of I. pavlovskyi ticks and I. persulcatus/ I. pavlovskyi hybrids as vectors, correct identification of tick species is necessary. The nuclear crt gene might be useful in distinguishing I. persulcatus from I. pavlovskyi ticks. Genetic variability in this gene has been studied and substantial differences between crt gene sequences of I. persulcatus and I. pavlovskyi ticks has been demonstrated. In this study, maximum-likelihood analysis showed that sequences of I. persulcatus and I. pavlovskyi ticks were identical or highly homologous among themselves. These results were confirmed by a Bayesian phylogeny. We conclude that crt gene sequences of I. persulcatus and I. pavlovskyi cannot be used for distinguishing these tick species and that the conflicting results of prior studies reflect samples from incorrectly identified ticks rather than real genetic differences between I. persulcatus and I. pavlovskyi.
在西西伯利亚南部地区，全沟硬蜱与帕氏硬蜱共存。这两种蜱类形态相似，并且已观察到全沟硬蜱和帕氏硬蜱之间存在自然杂交现象。为了研究帕氏硬蜱以及全沟硬蜱/帕氏硬蜱杂交种作为传播媒介的作用，准确鉴定蜱类物种是必要的。核crt基因可能有助于区分全沟硬蜱和帕氏硬蜱。已对该基因的遗传变异性进行了研究，并证明了全沟硬蜱和帕氏硬蜱的crt基因序列之间存在显著差异。在本研究中，最大似然分析表明，全沟硬蜱和帕氏硬蜱的序列彼此相同或高度同源。这些结果通过贝叶斯系统发育分析得到了证实。我们得出结论，全沟硬蜱和帕氏硬蜱的crt基因序列不能用于区分这两种蜱类物种，先前研究中相互矛盾的结果反映的是来自鉴定错误的蜱类样本，而非全沟硬蜱和帕氏硬蜱之间真正的遗传差异。
