Skip to main content
Premium Trial:

Request an Annual Quote

Maybe an RNA-DNA World

Both RNA and DNA molecules may have been involved in the emergence of life on Earth, according to New Scientist.

It notes that a common theory regarding how life began on Earth, dubbed RNA world, suggests that life here started out RNA-based and later switched to being DNA-based. But new results from researchers led by the MRC Laboratory of Molecular Biology's John Sutherland suggest RNA and DNA could have co-existed from the get-go. Previous work from the group had shown that pyrimidines could be made from prebiotic sources.

As they report in Nature, Sutherland and his colleagues uncovered a means of synthesizing the purine deoxyribonucleosides deoxyadenosine and deoxyinosine from sources that were likely around before life emerged on Earth. These results "offer fascinating experimental support for a mixed RNA–DNA world," add Kristian Le Vay and Hannes Mutschler from the Max Planck Institute of Biochemistry in a related Nature commentary

New Scientist notes that not everyone is convinced. "Is it harder for a pure RNA to learn to make DNA, or is it harder in John's DNA-RNA World to get a synthesis for the four missing [building blocks]?" Thomas Carell from the Ludwig Maximilian University of Munich tells it. "I don't know."