E-Mail An international team of scientists from the University of Turku, Finland and PennState University, USA have solved a long-standing mystery of how living organisms distinguish RNA and DNA building blocks during gene expression paving the way for the design of new antiviral drugs. The new insights were published in the journal Nature Communications. All cellular organisms use two types of nucleic acids, RNA and DNA to store, propagate and utilize their genetic information. The synthesis of DNA is carried out by enzymes called DNA polymerases and is needed to accurately transfer the genetic information from generation to generation. Synthesis of RNA is carried out by enzymes called RNA polymerases and is needed to utilize the genetic information to ultimately produce proteins that in turn fulfil most structural and catalytic functions in all modern-day living organisms.