What brings DNA to life, what gives it meaning, is the cellular environment in which it is embedded... Genetic theorists with little biochemical understanding have been profoundly misled by the metaphors that Crick provided in describing DNA (and RNA) as 'self-replicating' molecules or replicators, as if they could do it all by themselves. But they aren't and they can't... You may leave DNA or RNA for as long as you like in a test-tube and they will remain inert: they certainly won't make copies of themselves... The functioning cell, as a unit, constrains the properties of it's individual components. The whole has primacy over its parts
Steven Rose, Lifelines: Biology, Freedom, Determinism
As quoted by Mary Midgley