How did the first RNA or DNA molecules form?

The reason for this belief is that RNA uses a different sugar molecule in its nucleotides (which are a sugar molecule, a phosphate, and a nitrogen-base combined) than DNA, and it is easier to get to get these nucleotides to spontaneously form in laboratory environments that simulate early Earth. read more

The discovery in the 1960s that RNA could fold like a protein, albeit not into such complex structures, suggested an answer. If RNA could catalyse reactions as well as storing information, some RNA molecules might be capable of making more RNA molecules. read more