Richard Dawkins' The Selfish Gene was published in 1976. It promulgates a philosophy that places DNA firmly in charge; you are what your DNA (acting in its own evolutionary interests) tells you to be. We know of course that things are not so simple, but the enthusiasm that greets scientific advances in gene editing may reflect a subliminal wish to escape the implacable determinism of DNA. Biochemistry shows us how the environment influences genome function by acting on nucleosomes and their component histones. But, to build on this, we need to know to what extent environmentally induced changes can persist through mitosis and the germ line. The nucleosome and the modifications to which it is subject, offer a conceptual framework within which a heritable, environmentally sensitive epigenetic code might exist. If this can be proved, then we may finally escape the hegemony of DNA and realize the true potential of epigenetics.