Population Genetics of Promoter Sequences in Echinoids

Duke University, Durham NC

Investigators

Abstract

The genomes of all organisms contain DNA sequences called promoters that control gene expression. The goal of this project is to understand how these regulatory sequences vary genetically within populations. We will survey variation in regulatory sequences from several genes in the purple sea urchin, an animal model system that is particularly favorable for such analyses. We will then test the function of variant sequences for their ability to bind specific proteins that regulate gene expression. Finally, we will screen for promoter sequence variants that alter the timing of gene expression. Studies of human genetics have revealed extensive variation in promoter sequences and in their regulatory function. Our meta-analysis of this data, published earlier this year, was the first study to provide direct evidence that differences in regulatory sequences comprise a substantial fraction of the total functional genetic variation within a population. The current project will extend these studies in an organism where we can analyze an unbiased sample of genetic variation in regulatory sequences that has a functional impact. The results of these analyses will advance understanding of the population genetics of a portion of the genome that is functionally critical but understudied.