Animal Science Division, ICAR-Central Island Agricultural Research Institute, Port Blair 744 101, India.
J Genet. 2022;101.
The tick, is considered as the most notorious ectoparasite of veterinary importance in tropical and sub-tropical regions of the world. The present study deals with the molecular characterization of . in different regions of Andaman and Nicobar Islands using sequence information of mitochondrial cytochrome C oxidase subunit I (COX1) and their phylogenetic relationship with other Indian . genotypes. DNA polymorphism study identified a total of eight haplotypes with haplotype diversity of 0.909 ± 0.065 and nucleotide diversity of 0.01911 ± 0.00493. Currently, . complex consists of five taxa; . clade A sensu Burger . (2014), . clade B sensu Burger . (2014), . clade C sensu Low . (2015), . and . . Phylogenetic analysis revealed the presence of two clades (clade A and clade C) of . in Andaman and Nicobar isolates; Nicobar isolates belonged to clade A whereas Andaman isolates belonged to clade C of . complex. All the other Indian sequences retrieved from GenBank belonged to clade C of . complex. Andaman isolates under clade C of . were phylogenetically distinct from Indian isolates, which indicates independent speciation under isolated island milieu. In Indian isolates, no host-specific or geographical location-specific sub-clustering was observed which indicates the species jumping potential of the . tick. Therefore, this study indicated the presence of two different genetic makeup of . complex in two areas of the Andaman and Nicobar archipelago separated by a natural geographical barrier. This indicates presence of two different founding populations of ticks, one in the south and north-middle Andaman and the other in Nicobar Island.
蜱虫被认为是世界热带和亚热带地区最重要的兽医重要的外寄生虫。本研究使用线粒体细胞色素 C 氧化酶亚基 I（COX1）的序列信息对安达曼和尼科巴群岛不同地区的蜱虫进行了分子特征描述，并与其他印度蜱虫基因型进行了系统发育关系分析。DNA 多态性研究共鉴定出 8 种单倍型，单倍型多样性为 0.909 ± 0.065，核苷酸多样性为 0.01911 ± 0.00493。目前，蜱虫复合体由 5 个分类群组成；Burger（2014 年）的蜱虫 A 支系、Burger（2014 年）的蜱虫 B 支系、Low（2015 年）的蜱虫 C 支系、蜱虫和。系统发育分析显示，在安达曼和尼科巴群岛的分离株中存在两种蜱虫（A 支系和 C 支系）；尼科巴群岛的分离株属于 A 支系，而安达曼群岛的分离株属于蜱虫复合体的 C 支系。从 GenBank 中检索到的所有其他印度序列都属于蜱虫复合体的 C 支系。属于蜱虫复合体 C 支系的安达曼分离株在系统发育上与印度分离株不同，这表明在孤立的岛屿环境下独立的物种形成。在印度分离株中，没有观察到宿主特异性或地理位置特异性的亚聚类，这表明蜱虫具有物种跳跃的潜力。因此，本研究表明，在安达曼和尼科巴群岛的两个地区存在蜱虫复合体的两种不同遗传构成，这两个地区被天然地理屏障隔开。这表明存在两种不同的蜱虫种群，一种在中南部安达曼和另一种在尼科巴岛。
