Zhong Daibin, Menge David M, Temu Emmanuel A, Chen Hong, Yan Guiyun
Program in Public Health, College of Health Sciences, University of California, Irvine, California 92697, USA.
Genetics. 2006 Jul;173(3):1337-45. doi: 10.1534/genetics.105.055178. Epub 2006 Apr 19.
The yellow fever mosquito Aedes aegypti has been the subject of extensive genetic research due to its medical importance and the ease with which it can be manipulated in the laboratory. A molecular genetic linkage map was constructed using 148 amplified fragment length polymorphism (AFLP) and six single-strand conformation polymorphism (SSCP) markers. Eighteen AFLP primer combinations were used to genotype two reciprocal F2 segregating populations. Each primer combination generated an average of 8.2 AFLP markers eligible for linkage mapping. The length of the integrated map was 180.9 cM, giving an average marker resolution of 1.2 cM. Composite interval mapping revealed a total of six QTL significantly affecting Plasmodium susceptibility in the two reciprocal crosses of Ae. aegypti. Two common QTL on linkage group 2 were identified in both crosses that had similar effects on the phenotype, and four QTL were unique to each cross. In one cross, the four main QTL accounted for 64% of the total phenotypic variance, and digenic epistasis explained 11.8% of the variance. In the second cross, the four main QTL explained 66% of the variance, and digenic epistasis accounted for 16% of the variance. The actions of these QTL were either dominance or underdominance. Our results indicated that at least three new QTL were mapped on chromosomes 1 and 3. The polygenic nature of susceptibility to P. gallinaceum and epistasis are important factors for significant variation within or among mosquito strains. The new map provides additional information useful for further genetic investigation, such as identification of new genes and positional cloning.
由于埃及伊蚊具有重要医学意义且易于在实验室进行操作，它一直是广泛遗传研究的对象。利用148个扩增片段长度多态性（AFLP）标记和6个单链构象多态性（SSCP）标记构建了分子遗传连锁图谱。使用18对AFLP引物组合对两个正反交的F2分离群体进行基因分型。每对引物组合平均产生8.2个适合用于连锁图谱构建的AFLP标记。整合图谱的长度为180.9厘摩（cM），平均标记分辨率为1.2 cM。复合区间作图显示，在埃及伊蚊的两个正反交中，共有6个数量性状基因座（QTL）显著影响疟原虫易感性。在两个杂交组合中均鉴定出连锁群2上的两个共同QTL，它们对表型具有相似的影响，且每个杂交组合各有4个独特的QTL。在一个杂交组合中，4个主要QTL占总表型变异的64%，双基因上位性解释了11.8%的变异。在第二个杂交组合中，4个主要QTL解释了66%的变异，双基因上位性占16%的变异。这些QTL的作用方式为显性或超显性。我们的结果表明，至少有3个新的QTL定位在1号和3号染色体上。对鸡疟原虫易感性的多基因性质和上位性是蚊虫品系内或品系间显著变异的重要因素。新图谱为进一步的遗传研究提供了额外有用信息，如鉴定新基因和进行定位克隆。
