It is now apparent that an understanding of epigentic mechanisms such as DNA methylation is essential to providing insights to the control of cell differentiation as well as the development of a number genetic diseases and cancer.
In a study published in science the authors describe a role for RNAi dependent mechanism in the protection of transgenerational loss of DNA methylation in Arabidopsis.
Original article: A Role for RNAi in the Selective Correction of DNA Methylation Defects. Teixeira et al . Science 2009; Vol 323; No 5921; pp1600-1604.