Heritable variation between members of a population is normally attributed to genetic variation. Genes affecting fitness may be present or absent in different individuals or they may have dna mutations affecting their expression or the properties of the encoded protein. However, there are examples of heritable variation that are not associated with changes to the sequence of dna. Plants with differences in flower shape or fruit colour, for example, may have the same dna sequence.
I will describe recent research with plants that is unravelling the molecular basis of these epigenetic phenomena and its implications for agriculture and evolution.
Sir David Charles Baulcombe is currently Royal Society Research Professor and Regius Professor of Botany at the University of Cambridge. Baulcombe has helped unravel the complexities and origins of the different classes of small RNA molecule, and showed how they could determine patterns of epigenetic DNA methylation.