> Carell, an organic chemist, and his collaborators have now demonstrated a chemical pathway that — in principle — could have made A, U, C and G (adenine, uracil, cytosine and guanine, respectively) from basic ingredients such as water and nitrogen under conditions that would have been plausible on the early Earth. The reactions produce so much of these nucleobases that, millennium after millennium, they could have accumulated in thick crusts, Carell says. His team describes the results in Science on 3 October.

> The results add credence to the ‘RNA world’ hypothesis, says Carell, who is at the Ludwig Maximilian University of Munich in Germany. ...

It's worth noting that what was made were nucleobases - flat very low molecular weight molecules - that when attached to ribose yield nucleotides.

It is nucleotides, not nucleobases, that form RNA.

The "RNA world hypothesis" still needs to explain where the ribose came from, how it was joined with the bases that were supposedly littering the Earth's surface, and how the resulting nucleotides started spontaneously assembling themselves through combination with phosphate into polymers.

That's a very, very tall order in chemistry.