Abstract: Objective To investigate the difference in the sequence of cytochrome C oxidase subunit I (COI) gene in Ixodes persulcatus from the Heilongjiang Suifenhe and Jilin Yanbian ports in China and foreign countries, and to provide a basis for the prevention and control of tick-borne diseases. Methods From June 2013 to August 2016, a total of 106 I. persulcatus ticks were captured at Heilongjiang Suifenhe and Jilin Yanbian ports, among which 31 were selected to extract genomic DNA. PCR was used for the amplification of the COI gene, and then a homology analysis was performed, a phylogenetic tree was established, and a genetic distance analysis was performed for two geographical populations of I. persulcatus. Results The sequence of the COI gene in I. persulcatus from Heilongjiang Suifenhe and Jilin Yanbian ports had a homology of 99%-100% with the sequence of the COI gene in I. persulcatus from Russia and the Altai region in the border of Kazakhstan. The genetic distance of I. persulcatus from Suifenhe and Yanbian ports was ≤ 0.003. Conclusion The sequence of the COI gene in I. persulcatus from Suifenhe and Yanbian ports in China is highly consistent with that from neighboring countries. There may exist a high level of gene exchange or migration.

Key words: Population genetics, Homology, Genetic distance, Phylogenetic analysis

摘要： 目的 利用线粒体细胞色素C氧化酶亚基Ⅰ（COⅠ）基因对我国黑龙江省绥芬河、吉林省延边口岸全沟硬蜱的COⅠ基因序列和国外全沟硬蜱COⅠ序列进行分析对比研究，为了解蜱媒病及其防控奠定基础。方法 2013年6月至2016年8月从黑龙江省绥芬河口岸和吉林省延边口岸共采集全沟硬蜱106只，选取31只样本提取基因组DNA，采用PCR方法从蜱基因组中扩增COⅠ基因进行同源性分析，然后构建系统发生树，并对2个地理种群的全沟硬蜱进行遗传距离分析。结果 我国黑龙江省绥芬河口岸和吉林省延边口岸的全沟硬蜱COⅠ基因序列与俄罗斯多个地区同源性为99%～100%，与哈萨克斯坦边境口岸阿尔泰地区的全沟硬蜱COⅠ序列同源性也达到99%～100%；绥芬河口岸和延边口岸全沟硬蜱的遗传距离≤0.003。结论 我国绥芬河口岸和延边口岸的全沟硬蜱与周边邻近国家的全沟硬蜱COⅠ基因序列高度一致，可能存在极高的基因交流或迁移。

关键词: 种群遗传, 同源性, 遗传距离, 系统发生分析