Theoretical Studies in Ecological and Population Genetics

本研究将为理解和解释两种新的生物数据类型建立一个理论框架。第一个是基因搭便车。基因搭便车是指一个被选择的基因对同一染色体上其他没有被选择的基因的影响。对这些系统的动力学行为进行广泛的理论研究将有助于解决当前的实际问题，从推断选定基因的历史起源到解释分离两个DNA变体的物理距离之间经常缺乏相关性，以及它们观察到的非随机关联。这项研究也适用于目前在人类疾病基因附近发现的DNA序列中的许多可遗传变异，例如导致亨廷顿舞蹈病和囊性纤维化的基因，以及果蝇自然种群中的重要基因附近。另一条研究路线将为解释和利用涉及生物体遗传物质的两个组成部分的现有数据提供理论基础：一个通过双亲传递（核DNA），另一个通过单代遗传（例如，线粒体和叶绿体DNA）。在这两类遗传物质之间发现的重要的非随机关联，由于遗传模式的不同，可以为人类、动物和植物种群的进化史提供一种定性的新信息。为了利用这一独特的信息，广泛的理论研究将确定这两种遗传成分之间可能存在什么联系，以及什么力量或力量的组合将解释在自然种群中观察到的联系。将同时开发正式的统计程序，以便检验各种进化假设和估计重要的生物学参数，例如两个种群之间的迁移率。

This research will develop a theoretical framework for understanding and interpreting two new types of biological data. The first concerns genetic hitchhiking. Genetic hitchhiking refers to the effect of a selected gene upon other genes on the same chromosome which are not themselves under selection. An extensive theoretical study of the dynamical behavior of such systems will help resolve current practical problems ranging from deducing the historical origins of selected genes to explaining the frequent lack of correlation between the physical distance separating two DNA variants, and their observed nonrandom association. This investigation is also applicable to the many heritable variants in DNA sequences which are currently being found near disease genes in humans, such as those responsible for Huntington's chorea and cystic fibrosis, as well as near important genes in natural populations of Drosophila. The other line of research will provide a theoretical foundation for interpreting and exploiting current data involving two components of an organism's genetic material: one transmitted through both parents (nuclear DNA), the other uniparentally inherited (e.g., mitochondrial and chloroplast DNA). The significant nonrandom associations found between these two classes of genetic material can, because of the contrasting modes of inheritance, provide a qualitatively new kind of information about the evolutionary history of human, animal, and plant populations. In order to take advantage of this unique information, an extensive theoretical study will determine what associations are possible between these two genetic components, and what force or combination of forces would account for the observed associations in natural populations. Formal statistical procedures will be concurrently developed to allow the testing of various evolutionary hypotheses and the estimation of important biological parameters such as the migration rate between two populations.