Lanzaro G C, Zheng L, Toure Y T, Traore S F, Kafatos F C, Vernick K D
Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-0425, USA.
Insect Mol Biol. 1995 May;4(2):105-12. doi: 10.1111/j.1365-2583.1995.tb00014.x.
Microsatellites are defined as tracts of tandemly repeated short DNA sequences. Polymorphisms in this class of DNA are currently being used to generate a genetic map of the mosquito Anopheles gambiae. In the present study we explore the potential of microsatellites as a tool for studying the genetic structure of natural populations of this malaria vector. Genetic polymorphism at twenty enzyme coding gene loci and eleven microsatellite DNA loci was surveyed in a population of An. gambiae from Mali, West Africa. All of the microsatellite loci surveyed were polymorphic, as compared to 40% of the isozyme loci. The mean heterozygosity for the isozyme loci was only 0.097 (+/- 0.0035), but for the microsatellite loci it was 0.732 (+/- 0.060). The pattern of variability was very different between isozymes and microsatellites. Typically, at an isozyme locus a single allele occurred at a frequency > or = 0.75, whereas at microsatellite loci the most common allele had a frequency < 0.50. We conclude that microsatellites provide a rich source of genetic polymorphisms for the study of the population genetics of An. gambiae and are in many ways superior to isozymes for this purpose. We discuss the potential for utilizing genetically mapped microsatellite loci to explore the effect of chromosomal inversions on the distribution of genetic polymorphisms in An. gambiae.
微卫星被定义为串联重复的短DNA序列片段。这类DNA中的多态性目前正被用于构建冈比亚按蚊的遗传图谱。在本研究中，我们探索了微卫星作为研究这种疟疾媒介自然种群遗传结构工具的潜力。在来自西非马里的一群冈比亚按蚊中，对20个酶编码基因位点和11个微卫星DNA位点的遗传多态性进行了调查。与40%的同工酶位点相比，所有被调查的微卫星位点都是多态的。同工酶位点的平均杂合度仅为0.097（±0.0035），但微卫星位点的平均杂合度为0.732（±0.060）。同工酶和微卫星之间的变异模式非常不同。通常，在一个同工酶位点上，单个等位基因的出现频率≥0.75，而在微卫星位点上，最常见的等位基因频率<0.50。我们得出结论，微卫星为冈比亚按蚊群体遗传学研究提供了丰富的遗传多态性来源，并且在许多方面比同工酶更适合用于此目的。我们讨论了利用遗传定位的微卫星位点来探索染色体倒位对冈比亚按蚊遗传多态性分布影响的潜力。
