Recent technological advances have enabled large-scale analyses of molecular variation in natural populations. Very little is known, however, about the phenotypic consequences of this variation. The goal of this project is to understand the mechanisms that translate DNA sequence variation into phenotypic differences among individuals, using the Drosophila bab gene as a model. bab is responsible for a large proportion of variation in sexually dimorphic traits in natural populations. In this project, the entire bab genomic region will be sequenced from 100 Drosophila lines that show different phenotypes in order to identify DNA sequence changes associated with phenotypic variation. The level of bab gene product will then be quantified in the lines that show the greatest phenotypic differences, and the effects of each molecular polymorphism on gene activity will be determined. These data will be used to develop a quantitative model that links variation in DNA sequences to differences in individual development and, ultimately, in adult traits.
This project will facilitate the development of individualized approaches to human health by facilitating and understanding of the mechanisms that connect genetic variation to health and environment - that is, not only which DNA sequence changes are responsible for trait variation, but also how these changes produce different phenotypes, and why do they vary in nature. This work will also provide opportunities for undergraduate students to acquire first-hand research experience in evolutionary biology.