A Genomic Analysis of Complex Trait Variation in Mimulus

描述（申请人提供）：群体遗传学的主要目的是确定遗传变异的性质及其在自然群体中的维持方式。Mimulus guttatus是一种野花，在花的大小上表现出巨大的遗传变异，这种特征在物种复合体中广泛进化。我们将绘制一个单一的自然种群内的花大小的变化负责的遗传位点。guttatus和确定的大小和分布的等位基因的影响范围内的植物性状。实验将估计QTL的显性程度和模式以及与花大小等位基因相关的多效性效应。一个精简的育种计划将产生近等基因系（NIL），定位克隆的实际位点定义重要的QTL所必需的。它们还将用于田间和实验室研究，以测量单个QTL尺度上花大小变化的直接适合性后果。这些数据将被用来测试关于花大小变异的选择性维持的假设。结合以前和正在进行的研究结果，这些实验将提供一个详细的比较种间和种内的花形态的变化在M。点滴状种复合体重要的花QTL的定位克隆将允许重要的生态基因的分子群体遗传学研究。拟议的研究将通过教育和科学资源的开发产生更广泛的影响。

DESCRIPTION (provided by applicant): A primary objective of population genetics is to determine the nature of genetic variation and how it is maintained in natural populations. Mimulus guttatus is a wildflower that exhibits substantial genetic variation in flower size, a trait that has evolved extensively within the species complex. We will map the genetic loci responsible for variation in flower size within a single natural population of M. guttatus and determine the magnitude and distribution of allelic effects on a range of plant characters. The experiments will estimate the extent and pattern of dominance at QTL and the pleiotropic effects associated with flower size alleles. A streamlined breeding scheme will produce Nearly Isogenic Lines (NILs), necessary for positional cloning of the actual loci defining important QTL. They will also be used in field and lab studies to measure the direct fitness consequences of flower size variation at the scale of individual QTL. These data will be used to test hypotheses regarding the selective maintenance of flower size variation. Combined with results from previous and ongoing studies, these experiments will provide a detailed comparison of inter- and intra- specific variation in floral morphology within the M. guttatus species complex. Positional cloning of important floral QTLs will allow molecular population genetic studies of ecologically important genes. The proposed research will have broader impacts thorough both education and the development of scientific resources.