Mutational Effects on Quantitative Traits of Arabidopsis thaliana

9629457 Shaw自发突变是遗传变异的最终来源，遗传变异是由于选择和漂变而导致进化分歧的基础。关于影响多细胞生物数量性状的基因自发突变的进化后果的理论在过去的20年中已经得到了很好的发展。这项工作表明，突变的进化后果的推断取决于详细的信息，包括由于突变引起的变异的引入率，每个基因组的突变率，突变效应的分布，以及突变等位基因的基因作用。许多性状的突变率来源于容易检测到的效应（“可见突变”）的发生。然而，这些可能低估了进化上重要的突变率，因为它们没有考虑到影响较小的突变。经验研究，大多数集中在果蝇，提供了有关影响数量性状的突变方面的证据，其中一些方面的共识正在逐步形成。现有的关于其他生物的研究很少，其范围往往有限。特别是，从植物中获得的信息非常少，尽管它们为突变研究提供了明显的实验优势，因为代表不同世代的种子可以储存起来，以便最终在共同的环境中同时饲养。这里提出的实验旨在估计一年生十字花科植物，拟南芥中影响数量性状的突变的性质。 本研究将采用A. thaliana，以前已经从一个单一的创始人通过17代。所提出的实验将测定来自共同创始人的品系之间的变异，以及品系之间正式遗传杂交产生的后代之间的变异。 本研究的主要目的是：（1）推断突变影响的分布，（2）评估新出现的突变的遗传模式，（3）推断基因作用的参数，包括显性、上位性和多效性。

9629457 Shaw Spontaneous mutation is the ultimate source of genetic variation which is the basis for evolutionary divergence due to selection and drift. Theory concerning the evolutionary consequences of spontaneous mutation in genes affecting quantitative traits of multicellular organisms has been well developed over the past 20 years. This work has revealed that inference of the evolutionary consequences of mutation depends on detailed information, including the rate of introduction of variation due to mutation, per genome mutation rates, the distribution of mutational effects, and gene action of mutant allele. Mutation rate derived from the occurrence of readily detectable effects ('visible mutations') have been documented for many traits. These, however, likely underestimate rates of evolutionarily significant mutation because they fail to account for mutations of small effect. Empirical studies, most focusing on Drosophila melanogaster, have provided evidence concerning aspects of mutations affecting quantitative traits, and for some of these aspects consensus is gradually emerging. The few available studies on other organisms have tended to be limited in scope. In particular, very little information is available from plants, though they offer a clear experimental advantage for studies of mutation in that seeds representing distinct generations can be stored for eventual simultaneous rearing in a common environment. The experiments proposed here are designed to estimate the properties of mutations affecting quantitative traits in the annual crucifer, Arabidopsis thaliana. This study will employ lines of A. thaliana that have previously been advanced from a single founder through 17 generations. The proposed experiments will assay variation among lines derived from a common founder and also among progenies resulting from formal genetic crosses among lines. The major goals of this study are: (1 ) to infer distributions of mutational affects, (2) to assess the mode of inheritance of newly arising mutations, and (3) to infer the parameters of gene action, including dominance, epistasis, and pleiotropy.