Theoretical Population and Quantitative Genetics

吉莱斯皮许多分子进化研究的目标是理解为什么在物种之间和物种内个体之间的遗传物质，DNA中存在如此多的差异。在一种理论中，大多数这种变异没有功能后果。在这个项目正在研究的理论中，大多数这种变异确实有生物学后果。为了理解哪种理论和假设最能描述分子进化，我们将把每种理论的预测与实际DNA序列中观察到的模式进行比较。这项工作对理解人类疾病易感性等性状的遗传变异具有潜在价值。易感性的遗传变异是由于许多小突变还是几个大突变引起的？该项目第二部分的目标是定量遗传学，目的是了解物种内部和物种之间可测量特征（如大小或体重）变异的遗传基础。在这项工作中，最大的概念性问题是处理许多基因对数量性状的综合影响，每个基因的影响都很小。在待研究的理论中，这些小基因以一种增加生物相关性的方式相互作用，这在以前的模型中是缺失的。一旦该理论就位，它将被用于研究几个生物学问题。这项工作对农业很重要，因为农业从业者需要更好的关于性状遗传基础的理论，比如牛的产奶量，这些性状具有经济重要性。

9527808 GILLESPIE The goal of many studies of molecular evolution is to understand why there is so much variation in the genetic material, DNA, between species and between individuals within a species. In one theory most of this variation has no functional consequences. In the theory being studied in this project, most of this variation does have biological consequences. To understand which theory and assumptions best describe molecular evolution, the predictions of each theory will be compared with the patterns observed in actual DNA sequences. This work is of potential value for understanding genetic variation in such traits as disease susceptibility in human populations. Is genetic variation in susceptibility due to many small mutations or to a few large ones? The goal of the second part of this project, on quantitative genetics, is to understand the genetic basis of variation in measurable traits, such as size or weight, both within and between species. The great conceptual problem in this work is to deal with the combined effects of many genes, each of small effect, on a quantitative trait. In the theory to be investigated these small genes interact with one another in a way that adds biological relevance that was missing from previous models. Once the theory is in place, it will be used to investigate several problems of biological interest. This work will be important for agriculture, where practitioners require better theories of the genetic basis of traits, such as milk yield in cattle, that are of economic importance.