On Mutation: Darwin’s ‘whatever the cause’…

Abstract: Mutation is the source of genetic variation and fuels biological evolution. However, because mutations are relatively rare events, we have until recently known little about the frequencies, genomic distributions and molecular spectra of arising new mutations. This seminar will outline how a combined approach using mutation accumulation (MA) lineages of the model plant Arabidopsis thaliana, combined with whole genome sequencing and mutation-detection bioinformatics is advancing knowledge in this area. Spontaneous (background) mutational patterns will be compared with those characteristic of mutations induced by ionising radiation, of mutations associated with the ‘somaclonal variation’ characteristic of plants regenerated from in vitro cultured cells, or with mutations associated with growth in stressful environments. Finally, the mutational patterns observed in plants deficient for DNA mismatch repair will be outlined. The seminar will end with an exploration of overall understandings of mutation that can be drawn from these various examples.