Whole genome duplication – the gateway to adaptation?
Whole genome duplication (WGD, polyploidization) is arguably the most massive genome-wide mutation whose ubiquity across eukaryotes suggests an adaptive benefit, though no mechanism has been identified. Consequently, a large controversy dominates the field whether WGD represents net benefit or detriment to evolutionary success.
In this project, we are testing if WGD promotes adaptation in natural populations and address the underlying mechanism which remained unknown. We will build on our experimental and population genomic research in wild Arabidopsis that demonstrated that WGD can increase the capacity of populations to accumulate adaptive variation and the species is capable of parallel adaptation to multiple environmental challenges (alpine, serpentine).
To move beyond correlative studies, we will combine field surveys, population genomics and transplant experiments and address the adaptive consequences of WGD over a hierarchy of levels: genome, phenotype, population and species. Specifically, we will combine ecological genomics of natural populations of six diploid-autotetraploid plant species with short-term evolution experiments. To isolate the net effect of WGD we will also manipulate the mutation itself via synthesis of neo-polyploid lineages and compare adaptation signals in genomes and phenotypes of synthetic polyploids and their natural diploid and tetraploid relatives.
By determining the adaptive value of WGD, an important force in evolution and crop domestication, the project has the ambition to improve our understanding of the role of large genomic mutations in natural selection and adaptation.