Bridgett vonHoldt

Associate Professor | EEB
Evolutionary Genomics and Epigenetics
Office Phone
328 Moffett Laboratory

Domesticated species were the first genetic model systems, exemplified by classical genetic studies that examined the inheritance of phenotype variants. Yet, the full suite of molecular events that occur during domestication is still unknown. Being among the first domesticated species, canines are an ideal system to study genomic and phenotypic evolution. The domestic dog has a wide range of phenotypic diversity, nearly all of which is lacking in their gray wolf ancestor, and has been the focus of many gene mapping studies that have identified genes of large phenotypic effect as well as disease-associated variants. However, the evolutionary history of these traits has remained largely unexplored. What are the functional molecular changes that occurred during the domestication of the dog? What are the differences in genomic structure and transposon insertion sites found between the domestic dog and gray wolf genomes? Are gene expression differences in dogs associated with phenotypic diversification?

My research interests go beyond the scope of studying DNA variants and include other dimensions of the genome. The convergence of genome technologies and natural history hypotheses sets the stage for exploring traditional questions of behavioral ecology, population biology, and evolutionary history at multiple genomic levels. My research goal is to unravel genotype-phenotype evolution in both a naturally and artificially evolving species. I am specifically interested in the interaction of natural history phenotypes (e.g. social status, pigmentation, disease, fecundity, mating strategy) and gene expression changes and their regulation via epigenetic variation. Chromatin modification, differential methylation, microRNAs, and transcription factor binding can all have a profound effect on gene expression, initiating/silencing transcription, the degree of transcript stability, and splicing.