Science and Engineering 2 Building, Room 302
CatCast live link
Complex mutations, such as duplications, deletions, and chromosomal rearrangements are important sources of genetic novelty that can produce new genes. With recent improvements in genome sequencing, we are able to identify these mutations in a population genomic framework, describe their role in adaptation, and determine the ways their molecular effects influence their adaptive value. Using Drosophila as a genetic model where sequencing and analytical power is high, we find that chimeric genes created during duplication and rearrangement are commonly targets of positive selection. Thus, the evolution of genome content is unlikely to be driven primarily by nearly-neutral dynamics, in contradiction with previous theory on duplicate genes. These new chimeric gene structures often produce large-scale changes in gene expression, especially in the testes, putatively explaining their non-neutral effects.
Applying similar analyses in recent sequencing data for modern and archaic humans, we observe patterns of new gene creation and testis-specific expression, pointing to parallel roles of genome architecture changes in human evolution. Collectively, these results point to chimeric genes as mutations of large, nonneutral effect that can result in adaptive changes.
Rebekah Rogers is obsessed with the evolution of new genes. She studies how duplications and genome structure changes can shuffle gene fragments to create new genes. Dr. Rogers did her PhD with Daniel Hartl at Harvard University where she showed that chimeric genes, created from pieces of gene sequences, are a rich source of genetic novelty. These new gene sequences, which create new proteins with novel regulatory profiles, are often targets of natural selection. Dr. Rogers moved to a postdoc in Kevin Thornton’s lab at UC Irvine, developing bioinformatic methods to study the role of tandem duplications in evolution of non-model Drosophila species. She is now a postdoc working with Monty Slatkin and Rasmus Nielsen at UC Berkeley, where she works on genome structure changes and new gene formation in ancient
DNA of Archaic humans and woolly mammoths
For more information, please contact: