International Institute of Tropical Agriculture, Cotonou, 08 BP 0932, Benin.
University of Abomey Calavi, BP 526, Cotonou, Benin.
Malar J. 2020 Dec 17;19(1):456. doi: 10.1186/s12936-020-03503-2.
Understanding the molecular basis of insecticide resistance in mosquito, such as Anopheles funestus, is an important step in developing strategies to mitigate the resistance problem. This study aims to assess the role of the GSTe2 gene in DDT resistance and determine the genetic diversity of this gene in An. funestus.
Gene expression analysis was performed using microarrays and PCR while the potential mutation associated with resistance was determined using sequencing.
Low expression level of GSTe2 gene was recorded in Burkina-Faso samples with a fold change of 3.3 while high expression (FC 35.6) was recorded in southern Benin in Pahou (FC 35.6) and Kpome (FC 13.3). The sequencing of GSTe2 gene in six localities showed that L119F-GSTe2 mutation is almost getting fixed in highly DDT-resistant Benin (Pahou, Kpome, Doukonta) and Nigeria (Akaka Remo) mosquitoes with a low mutation rate observed in Tanongou (Benin) and Burkina-Faso mosquitoes.
This study shows the key role of the GSTe2 gene in DDT resistant An. funestus in Benin. Polymorphism analysis of this gene across Benin revealed possible barriers to gene flow, which could impact the design and implementation of resistance management strategies in the country.
了解蚊虫（如致倦库蚊）对杀虫剂产生抗药性的分子基础，是制定减轻抗药性问题策略的重要步骤。本研究旨在评估 GSTe2 基因在 DDT 抗性中的作用，并确定致倦库蚊 GSTe2 基因的遗传多样性。
使用微阵列和 PCR 进行基因表达分析，同时使用测序确定与抗性相关的潜在突变。
在布基纳法索的样本中，GSTe2 基因的表达水平较低，其 fold change 为 3.3，而在贝宁南部的帕霍和科波姆，其表达水平较高（FC 35.6）。对六个地点 GSTe2 基因的测序表明，L119F-GSTe2 突变在高度 DDT 抗性的贝宁（帕霍、科波姆、杜孔塔）和尼日利亚（阿卡卡雷莫）蚊虫中几乎固定，而在贝宁的塔农古和布基纳法索蚊虫中观察到的突变率较低。
本研究表明 GSTe2 基因在贝宁的 DDT 抗性致倦库蚊中起着关键作用。对该基因在贝宁的多态性分析显示，可能存在基因流动的障碍，这可能会影响该国抗药性管理策略的设计和实施。
