MUTATION, DRIFT, & THE RATE OF PHENOTYPIC EVOLUTION

突变、漂移、

• 批准号: 2178550
• 负责人: Michael R LYNCH
• 金额: $ 11.5万
• 依托单位: UNIVERSITY OF OREGON
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-08-01 至 1995-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2178550
• 关键词: Branchiopoda; Gastropoda; animal population genetics; biochemical evolution; computer simulation; corn; gene expression; genetic manipulation; genetic models; genetic polymorphism; mathematical model; molecular genetics; natural selections; plant population genetics; reproduction

This project is concerned with the long-term constraints on the rate of phenotypic evolution, particularly with the interaction of mutation and random genetic drift. Recent theoretical work has clarified the important contribution that polygenic mutation makes to the divergence of inbred lines, the response to long-term directional selection programs, and the maintenance of genetic variation under stabilizing selection. However, the practical utility of this theory is severely limited by a lack of rigorous. information on the properties of polygenic mutation. Using three model systems (the microcrustacean Daphnia, the snail Lymnaea, and corn), we plan to initiate long-term mutation-accumulation experiments in order to: 1) obtain estimates for the mutational rate of input of genetic variance (VM) and extent of dominance and pleiotropic effects of new mutations, and 2) test the hypotheses that the rate of polygenic mutation depends on generation time, frequency of meiosis, age of expression of characters, and genetic background. The proposed species and experimental protocols have been specifically selected in order to avoid the problems that have marred previous attempts to measure the properties of polygenic mutation and to help reveal whether existing estimates of VM are biased. In conjunction with the empirical work, analytical and numerical studies will be performed in order to develop quantitative genetic models that incorporate the joint interaction of finite population size, polygenic mutation, and selection. The sensitivity of the theoretical predictions to dominance, linkage, and pleiotropy will be evaluated. The long-term practical goals of the study are to provide the quantitative information necessary to: 1) predict the expected stability of asexual and homozygous lines that are becoming increasingly utilized in biomedical research, 2) determine the optimal designs of long-term selection programs and genetic conservation programs.

本项目关注的是 表型进化的速度，特别是与 突变和随机遗传漂变。 最近的理论工作 阐明了多基因突变的重要贡献 自交系的分歧，长期的反应， 定向选择计划，以及维持遗传 稳定选择下的变异 但是，实际 这个理论的实用性由于缺乏严格性而受到严重限制。 有关多基因突变特性的信息。 使用三 模型系统（微甲壳动物水蚤、蜗牛椎实螺和 玉米），我们计划启动长期的突变积累 实验，以便：1）获得突变的估计 遗传方差（VM）输入率和显性程度， 新突变的多效性效应; 2）检验假设 多基因突变的速率取决于世代时间， 减数分裂频率、性状表达的年龄和遗传 背景 提出的物种和实验方案 是专门挑选的，以避免出现的问题， 破坏了以前试图测量多基因 突变，并帮助揭示现有的VM估计是否 有偏见 结合实证工作，分析和 将进行数值研究，以开发 结合联合作用的定量遗传模型 有限的种群规模，多基因突变和选择。 的 理论预测对显性，连锁， 并评估多效性。 长期实际目标 研究的目的是提供必要的定量信息， 1）预测无性和纯合子的预期稳定性 越来越多地用于生物医学领域的生产线 研究，2）确定长期选择的最佳设计 基因保护计划和遗传保护计划。