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.

该项目关注的是对 表型演化的速率，特别是与 突变和随机遗传漂移。 最近的理论工作有 阐明了多基因突变的重要贡献 近交系的差异，对长期的反应 定向选择程序和遗传的维持 稳定选择下的变化。 但是，实用 该理论的效用受到缺乏严格的严格限制。 有关多基因突变特性的信息。 使用三个 模型系统（Microcrustacean洗礼症，蜗牛lymnaea和 玉米），我们计划启动长期突变蓄能 实验以：1）获得突变的估计值 遗传差异的投入率（VM）和优势程度 新突变的多效效应，以及2）检验假设 多基因突变的速率取决于生成时间， 减数分裂的频率，角色表达年龄和遗传 背景。 提出的物种和实验方案具有 专门选择以避免有问题的问题 损坏了以前测量多基因特性的尝试 突变并帮助揭示现有的VM估计值 有偏见。 结合经验工作，分析和 将进行数值研究以发展 融合关节相互作用的定量遗传模型 有限种群大小，多基因突变和选择。 这 理论预测对主导，联系的敏感性， 将评估多效性。 长期实践目标 该研究是为了提供必要的定量信息 TO：1）预测无性和纯合的预期稳定性 在生物医学中越来越多地利用的线条 研究，2）确定长期选择的最佳设计 计划和遗传保护计划。