Leitch and Bennett 1997

Leitch IJ, Bennett MD. 1997. Polyploidy in angiosperms. Trends in Plant Science 2: 470-476.

These authors reviewed the occurrence and patterns of polyploidy in angiosperms. The majority of “higher plants” apparently have polyploid ancestry, some quite recently reverted to diploid. Most polyploid plants appear to be allopolyploids, derived by hybridization. Allopolyploidy presents the possibility of multiple origins of hybrid polyploid taxa, which has been identified in a few species.

The evolution of duplicated genes is discussed, with an interesting section on homology-dependent gene silencing. This is a phenomenon possibly mediated by repeat-induced changes to chromatin structure, in which some copies within a gene family are silenced or their expression altered.