Department of Parasitology and Tropical Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China.
Exp Appl Acarol. 2011 May;54(1):51-63. doi: 10.1007/s10493-010-9419-z. Epub 2010 Dec 12.
To investigate the genetic specificity of Ixodes granulatus ticks collected from Taiwan, the genetic identities and phylogenetic relationships were analyzed by comparing the sequences of the internal transcribed spacer 2 (ITS2) region obtained from 27 strains of ticks representing twelve species of Ixodes. Five major clades can be easily distinguished by neighbour-joining analysis and were congruent by maximum-parsimony method. All these I. granulatus ticks collected from Taiwan and Japan were genetically affiliated to a monophyletic group with highly homogeneous sequences (95.8-99.5% similarity), and can be discriminated from other species and subgenera of Ixodes ticks with a sequence divergence ranging from 13.6% to 62.9%. Moreover, interspecific analysis revealed that four distinct lineages are evident between Ixodes ticks, and all these I. granulatus ticks collected from Taiwan and Japan belong to the same lineage. Our results provide the first investigation on the genetic specificity of I. granulatus ticks, and demonstrate that all these I. granulatus ticks represent a unique lineage distinct from other species and subgenera of Ixodes ticks. The feasibility of ITS2-based genetic analysis for species-specific identification of I. granulatus ticks around East Asia was highly anticipated.
为了探究从台湾地区采集的硬蜱的遗传特异性，通过比较代表十二种硬蜱属的 27 株蜱的内部转录间隔区 2（ITS2）序列，分析了其遗传身份和系统发育关系。通过邻接法分析可以轻松区分出 5 个主要分支，最大简约法分析也证实了这些分支的一致性。所有这些从台湾和日本采集的硬蜱均与一个单系群具有高度同源的序列（95.8-99.5%的相似度），可以与其他硬蜱属种和亚属区分开来，其序列差异范围为 13.6%至 62.9%。此外，种间分析表明，硬蜱之间存在四个明显的谱系，所有从台湾和日本采集的硬蜱均属于同一谱系。本研究首次对硬蜱的遗传特异性进行了调查，表明所有这些从台湾和日本采集的硬蜱均代表一个独特的谱系，与其他硬蜱属种和亚属不同。基于 ITS2 的遗传分析对于东亚地区硬蜱属种特异性鉴定的可行性值得期待。
