Inherited epigenetic variation — revisiting soft inheritance


Phenotypic variation is traditionally parsed into components that are directed by genetic and environmental variation. The line between these two components is blurred by inherited epigenetic variation, which is potentially sensitive to environmental inputs. Chromatin and DNA methylation-based mechanisms mediate a semi-independent epigenetic inheritance system at the interface between genetic control and the environment. Should the existence of inherited epigenetic variation alter our thinking about evolutionary change?

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Figure 1: Three classes of epigenetic variation.


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I am grateful for the helpful comments of G. Allen and the anonymous reviewers. My laboratory's experimental work on epigenetic variation and inheritance is funded by the US National Science Foundation.

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Richards, E. Inherited epigenetic variation — revisiting soft inheritance. Nat Rev Genet 7, 395–401 (2006).

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