RUI: On the Origin of Genetic Variation: Investigating the Causes of Variation In Mutation Rates and Spectra

Understanding how genetic variation between individuals is generated is necessary for both applied and general biology. The origin of genetic variation is fundamental to the maintenance and generation of biodiversity. It influences our view of how humans and other species adapt in a changing world and can shape how we approach prevention of pathogen outbreaks. Mutation is the ultimate source of variation but surprisingly variation in mutation rates is poorly understood. This research will take advantage of advances in genomic screening to examine what are the causes, rates, and types of mutation that occur naturally using a direct, experimental approach. In addition to increased understanding of processes important to human health and safety, broader impacts will be provided through training materials and networking opportunities for young scientists across multiple institutions and career stages. The experiments will focus on quantifying variation at three scales: locally, genome-wide, and across space over long time periods. Multiple factors that may shape mutation profiles will be individually tested and evaluated to see what role they play in generating genetic variation at those scales. Those factors include generation time, developmental trajectories, transcription rates, recombination frequencies, and an array of other mechanisms that can be experimentally manipulated in a multicellular eukaryote, Daphnia. Multiple species of microcrustaceans from that genus, a widely-studied model group, will provide an opportunity to compare the relative contributions of those factors in an ‘all else equal’ context unavailable in broader studies conducted across the tree of life. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.