Genome dynamics of yeast parental species and hybrids in the context of experimental evolution

In a previous study (Bautista, 2021), F1 hybrids were generated between the budding yeast species Saccharomyces cerevisiae and S. paradoxus to assess their adaptive potential in an environment simulating UV radiation. The results of replicated experimental evolution spanning 100 generations revealed that hybrids exhibited a diminished adaptive potential compared to their parental strains. Subsequently, we delved into the underlying genomic factors contributing to these distinct adaptive rates in hybrids. We performed whole-genome sequencing (WGS) on 270 ancestral and evolved hybrid and parental lines to investigate major genomic changes in copy number, such as ploidy changes or aneuploidies, and to identify potentially distinctive de novo mutations in hybrids when contrasted with their parental counterparts.