1. Waddington, C. H. (1942) The epigenotype. Endeavour 1, 18–20.
2. Tost, J. (2008) Epigenetics, Horizon Scientific Press, Norwich, UK.
3. Kouzarides, T. (2007) Chromatin modifications and their function. Cell 128, 693–705.
4. Nightingale, K. P., O’Neill, L. P., Turner, B. M. (2006) Histone modifications: signalling receptors and potential elements of a heritable epigenetic code. Curr Opin Genet Dev 16, 125–136.
5. Bird, A. (2002) DNA methylation patterns and epigenetic memory. Genes Dev 16, 6–21.