Dissertation Research: Overdominance and the Maintenance of Genetic Variation for Fitness

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

Genetic variation affecting survival and reproductive success appears to be common in animal populations and is paradoxical because natural selection is expected to eliminate harmful genetic variants from the gene pool. Understanding the processes maintaining such widespread fitness variation is a major goal of evolutionary biology research. The proposed research merges population genetics theory with experiments on X-chromosome fitness variation in the fruit fly (Drosophila melanogaster) to test an influential model of fitness variation - overdominant selection - that maintains genetic diversity by favoring individuals that are genetically variable. By focusing on X-linked variation, patterns associated with the overdominant selection process can be disentangled from potentially obscuring patterns produced by other evolutionary processes. This research will shed light on the role of selection in preserving population genetic variation, and will have important implications for related biological disciplines, particularly those aiming to mitigate the negative effects of inbreeding (e.g., animal husbandry and wildlife conservation), or understand the causes and persistence of human genetic disease. The project also provides a wealth of opportunities for teaching and introducing undergraduate students to original research.