Researchers at Penn State University have developed a chemical model that mimics a possible step in the formation of cellular life on Earth four-billion years ago. Using large “macromolecules” called polymers, the scientists created primitive cell-like structures that they infused with RNA – the genetic coding material that is thought to precede the appearance of DNA on Earth – and demonstrated how the molecules would react chemically under conditions that might have been present on the early Earth. The journal Nature Chemistry posted the research as an Advance Online Publication.

In modern biology, all life, with the exception of some viruses, uses DNA as its genetic storage mechanism. According to the “RNA-world” hypothesis, RNA appeared on Earth first, serving as both the genetic-storage material and the functional molecules for catalyzing chemical reactions, then DNA and proteins evolved much later.