Polyploidy and genome restructuring: a variety of outcomes.

Dramatic genome rearrangement has been observed after whole genome duplication (WGD) in some plant species, leading many to suggest that genome restructuring may be a common consequence of WGD. However, recent analyses of ancient WGDs in yeast and vertebrates have not shown any evidence for increased rearrangement after WGD. When WGD events across all three kingdoms of eukaryotic life are considered-including plants, yeast, vertebrates, and human cancers-we find that a variety of outcomes are possible, from genome restructuring to genome stasis. In fact, striking differences in genome change after WGD can be observed within single plant genera, indicating that there are no simple rules that can predict a genome's reaction to WGD.