Dixit Jyotsana, Arunyawat Uraiwan, Huong Ngo Thi, Das Aparup
Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, Sector-8, Dwarka, New Delhi, 110077, India.
Mol Ecol. 2014 Nov;23(22):5599-618. doi: 10.1111/mec.12943. Epub 2014 Oct 30.
Utilization of multiple putatively neutral DNA markers for inferring evolutionary history of species population is considered to be the most robust approach. Molecular population genetic studies have been conducted in many species of Anopheles genus, but studies based on single nucleotide polymorphism (SNP) data are still very scarce. Anopheles minimus is one of the principal malaria vectors of Southeast (SE) Asia including the Northeastern (NE) India. Although population genetic studies with mitochondrial genetic variation data have been utilized to infer phylogeography of the SE Asian populations of this species, limited information on the population structure and demography of Indian An. minimus is available. We herewith have developed multilocus nuclear genetic approach with SNP markers located in X chromosome of An. minimus in eight Indian and two SE Asian population samples (121 individual mosquitoes in total) to infer population history and test several hypotheses on the phylogeography of this species. While the Thai population sample of An. minimus presented the highest nucleotide diversity, majority of the Indian samples were also fairly diverse. In general, An. minimus populations were moderately substructured in the distribution range covering SE Asia and NE India, largely falling under three distinct genetic clusters. Moreover, demographic expansion events could be detected in the majority of the presently studied populations of An. minimus. Additional DNA sequencing of the mitochondrial COII region in a subset of the samples (40 individual mosquitoes) corroborated the existing hypothesis of Indian An. minimus falling under the earlier reported mitochondrial lineage B.
利用多个假定为中性的DNA标记来推断物种种群的进化历史被认为是最可靠的方法。已经在许多按蚊属物种中开展了分子群体遗传学研究，但基于单核苷酸多态性（SNP）数据的研究仍然非常稀少。微小按蚊是东南亚包括印度东北部的主要疟疾传播媒介之一。尽管利用线粒体遗传变异数据进行的群体遗传学研究已被用于推断该物种东南亚种群的系统地理学，但关于印度微小按蚊种群结构和种群统计学的信息有限。我们在此开发了一种多位点核遗传方法，该方法利用位于微小按蚊X染色体上的SNP标记，对八个印度种群样本和两个东南亚种群样本（总共121只蚊子）进行分析，以推断种群历史并检验关于该物种系统地理学的几个假设。虽然泰国微小按蚊种群样本呈现出最高的核苷酸多样性，但大多数印度样本也具有相当高的多样性。总体而言，微小按蚊种群在覆盖东南亚和印度东北部的分布范围内存在适度的亚结构，主要分为三个不同的遗传簇。此外，在目前研究的大多数微小按蚊种群中都能检测到种群扩张事件。对一部分样本（40只蚊子）的线粒体COII区域进行的额外DNA测序证实了现有的关于印度微小按蚊属于先前报道的线粒体谱系B的假设。
