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

University Of Texas At Austin, Austin TX

Investigators

Abstract

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.