What I always feared, but couldn’t believe, is now confirmed by renowned experts in a new Cell editorial
Historically, the word “epigenetics” was used to describe events that could not be explained by genetic principles.
It goes back to Conrad Waddington – and describes now such bizarre and inexplicable features like paramutation in maize, position effetc variegation in Drosophila and methylation in humans. There is a nice analogy of the classical 1957 epigenetic landscape figure of Waddington where the course of the ball is influenced by hillls and valleys where it finally arrives – the Pinball arcade game
known factors that may regulate epigenetic phenomena are shown direcing the complex movements of pinballs (cells) across the elegant landscape … no specific order of molecular events is implied; as such a sequence remains unknown. Effector proteins recognize specific histone modifications…