Editor's Summary

11 May 2006

Counting the cost

Methylation and other alterations to DNA can significantly alter gene activity, causing inter-individual variation and sometimes disease, notably cancers. Such changes are 'epigenetic', and the term 'epigenome' refers to all the heritable biological factors other than DNA sequence that influence gene expression. Proposals for a large-scale Human Epigenome Project, modelled on the Human Genome Project, have provoked heated debate. Can this multimillion-dollar project be justified?

News FeatureEpigenetics: Unfinished symphony

To correctly 'play' the DNA score in our genome, cells must read another notation that overlays it — the epigenetic code. A global effort to decode it is now in the making, reports Jane Qiu.