New research could upend widely accepted theory on RNA-centric origin of cellular life Experts say a commonly held theory of the origins of cellular life could be wrong It was thought that RNA was the basis from which DNA and cells developed But new research shows both DNA and RNA could've existed at the same time A compound called thiouridine may have been the catalyst, researchers say By James Pero For Dailymail.com Published: 21:01 BST, 3 April 2019 | Updated: 21:01 BST, 3 April 2019 Viewcomments A long-held and popular theory of the precursor to cellular life could be turned upside down, as researchers have claimed in a new study that RNA and DNA may have originally existed together. Their claims clash with a widely accepted theory that cellular lifeforms as we know them developed from RNA — previously considered to be the building block to DNA. The findings were published by researchers at Scripps in the journal Nature Chemistry. Scroll down for video A new discovery about RNA shows that the origins of life cellular life as we know them may have a different background. Researchers say RNA and DNA may have existed together 'These new findings suggest that it may not be reasonable for chemists to be so heavily guided by the RNA World hypothesis in investigating the origins of life on Earth,' said co-principal investigator Ramanarayanan Krishnamurthy, PhD, associate professor of chemistry at Scripps Research. If true, the researchers findings would not just realign common understanding of life before cellular organisms, but also illuminate a longtime scientific mystery of how RNA could have developed into DNA. Previously, chemists hypothesized that RNA — which they thought arose before DNA due to its more basic and versatile nature — could have been converted to DNA by an unknown enzyme, but researchers have identified a new compound present during life's origin that could have been a catalyst. The compound, called thiouridine, via a few plausible chemical reaction steps, could have been converted into either DNA or RNA, the researchers say. These two fundamental building blocks for cellular life could have even combined together to create the first ever genes, sorting themselves by their strengths and weaknesses like we see today. Scientists said that DNA is perfect for the storing of long term genetic information while RNA is exceptionally good at transporting genetic information and making proteins. Scientists said that DNA is perfect for the storing of long term genetic information while RNA is exceptionally good at transporting genetic information and making proteins RNA is also structurally similar to DNA, except one of the four fundamental pieces, thymine, is substituted for uracil. This changes the shape and structure of the molecule and researchers have long believed this chemical was vital to the development of Earth's first lifeforms. Recently, an accidental discovery by Harvard academics published in December 2018 found that a slightly different version of RNA may have been the key ingredient allowing life on Earth to blossom. However, the theory did not account for recent discoveries. 'There is the beginning of a realization in the field that RNA and DNA could have been mixed together initially but later separated according to the things they do best,' Krishnamurthy said. Share or comment on this article: All rights reserved for this news site dailymail and under his responsibility