中国登革热媒介白纹伊蚊的种群遗传多样性分析

Population genetic diversity analysis of the dengue vector Aedes albopictus in China

目的白纹伊蚊是中国登革热的本土主要传播媒介,了解白纹伊蚊的种群空间遗传结构、迁移和基因流动,对于有效防控病媒传播疾病至关重要。方法于2023年6—9月在中国热带、亚热带和温带的8个不同地理地点采集蚊虫并进行形态学鉴定。从单只雌蚊中提取基因组DNA,对线粒体细胞色素C氧化酶Ⅰ基因进行扩增和测序。使用BioEdit、DnaSP version 6、Arlequin 3.5、Mega 11等软件评估了种群遗传多样性和相关种群特征。结果3个气候区的8个白纹伊蚊种群共成功测序233个样本,获得了632 bp的基因片段序列,有19个可变位点,无插入和缺失突变。共检测到21个单倍型,H4是3种气候类型的优势共享单倍型。单倍型多样性(Haplotype diversity,Hd)为0.191(北京种群)~0.887(西双版纳种群),核苷酸多样性(Nucleotide diversity,Pi)为0.00051(北京种群)~0.00298(西双版纳种群),提示白纹伊蚊具有较高的单倍型多样性和较低的核苷酸多样性。遗传分化指数为0.026~0.641,其中,温带地区与热带/亚热带地区的遗传分化较高。分子变异分析支持遗传分化主要来自种群内(60.45%)。结论热带地区的生态和气候环境使白纹伊蚊具有更高的遗传多样性,人类活动加剧了不同气候区传播登革热的风险。

Objective Aedes albopictus is the main indigenous vector of dengue fever in China.Understanding the spatial genetic structure of Aedes albopictus populations,migration,and gene flow is crucial for the effective prevention and control of vector-borne diseases.Methods From June to September 2023,mosquitoes were collected and morphologically identified from eight different geographic locations across tropical,subtropical,and temperate zones of China.Genomic DNA was extracted from individual female mosquitoes,and the mitochondrial cytochrome C oxidase I gene was amplified and sequenced.Population genetic diversity and associated population characteristics were assessed using software such as BioEdit,DnaSP version 6,Arlequin 3.5,and Mega 11.Results A total of 233 samples from eight Aedes albopictus populations across the three climatic zones were successfully sequenced,yielding a gene fragment sequence of 632 bp with 19 variable sites and no insertion or deletion mutations.A total of 21 haplotypes were detected,with H4 being the dominant shared haplotype among the three climate types.Haplotype diversity(Hd)ranged from 0.191(Beijing population)to 0.887(Xishuangbanna population),and nucleotide diversity(Pi)ranged from 0.00051(Beijing population)to 0.00298(Xishuangbanna population),suggesting high haplotype diversity and low nucleotide diversity in Aedes albopictus.The genetic differentiation indices ranged from 0.026 to 0.641,with higher genetic differentiation between temperate and tropical/subtropical regions.The analysis of molecular variation supported that genetic differentiation mainly came from within populations(60.45%).Conclusions The ecological and climatic environment in the tropics results in higher genetic diversity of Aedes albopictus.Human activities have exacerbated the risk of dengue transmission across different climatic zones.