Temu Emmanuel A, Yan Guiyun
Department of Biological Sciences, State University of New York at Buffalo, Buffalo, New York 14260, USA.
Am J Trop Med Hyg. 2005 Oct;73(4):726-33.
The population genetic structure of the African malaria vector Anopheles arabiensis from western Kenya, the Great Rift Valley, and coastal Kenya was investigated using 12 microsatellite loci and a partial sequence of mtDNA dehydrogenase gene subunit 5 (ND5). The mean number of alleles and the observed heterozygosity were similar for the mosquito populations from the three regions as revealed by the microsatellite data. A total of 30 polymorphic sites in the ND5 gene defined 39 haplotypes. Six haplotypes were shared among four populations from the three distinct ecological conditions, and they constituted 92% of the total number of individuals sequenced. Mitochondrial haplotype and nucleotide diversity were high. Microsatellite markers within polymorphic inversions revealed a level of genetic differentiation (F(ST) = 0.116) four to seven times higher than markers outside inversions (F(ST) = 0.016) or inside fixed inversions (F(ST) = 0.027). Mitochondrial ND5 gene sequences did not reveal significant genetic differentiation for the same four populations (phi(ST) = -0.008). The contrasts in the level of genetic differentiation between microsatellite markers inside polymorphic inversions, the mitochondrial ND5 gene, and microsatellite markers outside inversions suggest that the level of genetic differentiation in An. arabiensis populations across the Great Rift Valley varies significantly among different areas of the genome. Variations in the degree of genetic differentiation with respect to the chromosomal location of microsatellite markers may result from intrinsic characteristics of the markers, demographic or historic factors affecting these populations, and the possible adaptive significance of chromosomal inversions to climatic conditions.
利用12个微卫星位点和线粒体DNA脱氢酶基因亚基5（ND5）的部分序列，对来自肯尼亚西部、东非大裂谷和肯尼亚沿海地区的非洲疟疾媒介阿拉伯按蚊的群体遗传结构进行了研究。微卫星数据显示，来自这三个地区的蚊虫群体的平均等位基因数和观察到的杂合度相似。ND5基因中共有30个多态性位点，定义了39种单倍型。在来自三种不同生态条件的四个群体中共有六种单倍型，它们占测序个体总数的92%。线粒体单倍型和核苷酸多样性很高。多态性倒位内的微卫星标记显示出的遗传分化水平（F(ST)=0.116）比倒位外的标记（F(ST)=0.016）或固定倒位内的标记（F(ST)=0.027）高四到七倍。线粒体ND5基因序列未显示相同四个群体之间存在显著的遗传分化（phi(ST)= -0.008）。多态性倒位内的微卫星标记、线粒体ND5基因和倒位外的微卫星标记之间遗传分化水平的差异表明，大裂谷地区阿拉伯按蚊群体的遗传分化水平在基因组的不同区域之间存在显著差异。微卫星标记的遗传分化程度相对于染色体位置的变化可能是由于标记的内在特征、影响这些群体的人口统计学或历史因素，以及染色体倒位对气候条件可能的适应性意义。
