Before DNA became Earth's primary genetic material, early forms of life are believed to have used RNA to encode genetic instructions. But what was doing the job before RNA came on the scene?
The prospect of artificial life has just come one step closer, with the discovery that a synthetic version of DNA and RNA can evolve like the real thing.
For ten years, it's been known that RNA interference could potentially kill cancer by shutting off malfunctioning genes - but there's been no efficient way to deliver the RNA.
