Editor's Summary
12 January 2006
War of the worlds
In life's early days, most biologists believe, there was no DNA; instead, life stored its information in RNA, a versatile molecule that can also act as an enzyme. So how did DNA eventually take over this 'RNA world'? Evolutionary biologist Patrick Forterre suggests that viruses, not cells, triggered the change, adopting DNA not because of its merits as an information store but because it allowed them to evade the defences of RNA-based cells. The rest is evolutionary history.
News Feature: Origins of DNA: Base invaders
Could viruses have invented DNA as a way to sneak into cells? John Whitfield investigates.
doi:10.1038/439130a
