DISSERTATION RESEARCH: The Impact of Ploidy, Heterozygosity, and the Environment on Mutational Effects in Yeast

这项研究将调查酿酒酵母中突变的影响。当突变以单拷贝(杂合)或成对(纯合子)发生时，研究人员将测量这些影响。研究的第二阶段将比较突变如何影响生命阶段的生存和生殖，在生命阶段，每个人每条染色体(二倍体)都有两个副本，而当他们只有一个(单倍体)时。该项目的第三个组成部分将估计影响生存和生殖的新突变进入基因组的速度。新的突变是决定生物体衰老的主要因素之一，为什么繁殖密切相关的个体往往产生繁殖减少的后代，以及为什么许多生物体进行有性繁殖。尽管这些话题对人类健康和遗传学很重要，但对突变率及其影响的分布的估计一直很难产生。酵母，酿酒酵母，是一个无与伦比的系统，在其中估计这些参数。除了提高我们对突变特性的一般理解外，这些估计也将适用于农业和保护生物学。

The research will investigate the effects of mutations in the yeast, Saccharomyces cerevisiae. The investigators will measure these effects when mutations occur as single copies (heterozygous) or in pairs (homozygous). A second phase of the research will compare how mutations affect survival and reproduction in the life phase where individuals have two copies of every chromosome (diploid) vs. when they have one (haploid). A third component of the project will estimate the rate at which new mutations that affect survival and reproduction enter the genome. New mutations are one of the primary factors that determine why organisms age, why breeding closely related individuals often yields offspring with reduced reproduction, and why many organisms reproduce sexually. Despite the importance of these topics for human health and genetics, estimates of mutation rates and the distribution of their effects have been very difficult to generate. The yeast, Saccharomyces cerevisiae, is an unparalleled system in which to estimate these parameters. In addition to improving our general understanding of the properties of mutations, these estimates will also be applicable to agriculture and conservation biology.