Lai C, Lyman R F, Long A D, Langley C H, Mackay T F
Center for Population Biology, University of California at Davis 95616.
Science. 1994 Dec 9;266(5191):1697-702. doi: 10.1126/science.7992053.
The association between quantitative genetic variation in bristle number and molecular variation at a candidate neurogenic locus, scabrous, was examined in Drosophila melanogaster. Approximately 32 percent of the genetic variation in abdominal bristle number (21 percent for sternopleural bristle number) among 47 second chromosomes from a natural population was correlated with DNA sequence polymorphisms at this locus. Several polymorphic sites associated with large phenotypic effects occurred at intermediate frequency. Quantitative genetic variation in natural populations caused by alleles that have large effects at a few loci and that segregate at intermediate frequencies conflicts with the classical infinitesimal model of the genetic basis of quantitative variation.
在黑腹果蝇中，研究了刚毛数量的数量遗传变异与候选神经发生位点“粗糙”处的分子变异之间的关联。在来自自然种群的47条第二染色体中，腹部刚毛数量的遗传变异约32%（腹侧刚毛数量为21%）与该位点的DNA序列多态性相关。几个与大表型效应相关的多态性位点以中等频率出现。由少数位点上具有大效应且以中等频率分离的等位基因引起的自然种群中的数量遗传变异，与数量变异遗传基础的经典微效多基因模型相冲突。
