Ravel S, de Meeus T, Dujardin J P, Zézé D G, Gooding R H, Dusfour I, Sané B, Cuny G, Solano P
IRD UR 177, Laboratoire de Recherche et de Coordination sur les Trypanosomoses IRD/CIRAD, Campus de Baillarguet, 34398 Montpellier Cedex 5, France.
Infect Genet Evol. 2007 Jan;7(1):116-25. doi: 10.1016/j.meegid.2006.07.002. Epub 2006 Aug 4.
Glossina palpalis is the main vector of human African trypanosomosis (HAT, or sleeping sickness) that dramatically affects human health in sub-Saharan Africa. Because of the implications of genetic structuring of vector populations for the design and efficacy of control campaigns, G. palpalis palpalis in the most active focus of sleeping sickness in Côte d'Ivoire was studied to determine whether this taxon is genetically structured. High and statistically significant levels of within population heterozygote deficiencies were found at each of the five microsatellite loci in two temporally separated samples. Neither null alleles, short allele dominance, nor trap locations could fully explain these deviations from random mating, but a clustering within each of the two samples into different genetic sub-populations (Wahlund effect) was strongly suggested. These different genetic groups, which could display differences in infection rates and trypanosome identity, were composed of small numbers of individuals that were captured together, leading to the observed Wahlund effect. Implications of this population structure on tsetse control are discussed.
须舌蝇是人类非洲锥虫病（HAT，即昏睡病）的主要传播媒介，该病对撒哈拉以南非洲地区的人类健康造成了严重影响。由于病媒种群的遗传结构对控制活动的设计和效果具有重要意义，因此对科特迪瓦昏睡病最活跃疫源地的须舌蝇进行了研究，以确定该分类单元是否存在遗传结构。在两个时间上分开的样本中，五个微卫星位点中的每一个都发现了较高且具有统计学意义的种群内杂合子缺陷水平。无效等位基因、短等位基因显性或诱捕地点均无法完全解释这些偏离随机交配的现象，但强烈表明两个样本中的每一个都聚类为不同的遗传亚群（瓦伦德效应）。这些不同的遗传群体可能在感染率和锥虫种类上存在差异，它们由少量一起捕获的个体组成，从而导致了观察到的瓦伦德效应。本文讨论了这种种群结构对采采蝇控制的影响。
