Collaborative Research: Theoretical and empirical investigation of mutation rate evolution driven by variation in reproductive mode

DNA mutation is a fundamental biological process that drives evolution, adaptation, and human health challenges such as cancer and antibiotic resistance. Understanding how and why mutation rates vary across cells, organelles, and species remains a major open question in biology. This project investigates how mode of reproduction shapes the evolution of mutation rate. By determining how reproductive strategies influence the origin of new genetic variation, this research provides foundational insights that can help predict how natural populations will adapt to novel environments and assist in managing invasive species, which are frequently clonal or highly self-fertilizing. Because human cells proliferate clonally, understanding mutational processes in clonal lineages sheds light on aging and cancer development. This project also supports education and public engagement by providing STEM activities for communities in Iowa and Texas. This initiative will also train graduate, undergraduate, and high school students, offering them vital career development and mentorship in science and community outreach and building a biotechnology workforce. The primary goal of this project is to model and empirically test the evolutionary consequences of reproductive mode variation on mutation rates. The project aims to build on the drift-barrier hypothesis to develop new theory exploring the short- and long-term impacts of reproductive mode variation, polyploidy, and beneficial mutations on mutation rate evolution. Empirically, the research measures base-pair substitution and structural mutation rates across three different types of organisms that have undergone independent transitions in reproductive mode. The study systems include the snail Potamopyrgus antipodarum (outcrossing to obligate clonal), the ciliate Tetrahymena (facultative outcrossing to clonal), and plants in the Brassicaceae family (outcrossing to highly selfing). The investigators will use mutation accumulation experiments and parent-offspring analyses, combined with whole-genome sequencing, to estimate de novo mutation rates and mutational spectra. By comparing mutation parameters in closely related lineages with multiple independent transitions in reproductive strategies, this project will help illuminate factors driving mutation rate variation 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. NSF Award ID: 2535706 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Ricardo Azevedo | Institution: University of Houston, HOUSTON, TX | Award Amount: $997,996 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2535706 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2535706.html