Before DNA, scientists believe that the molecule that encoded genetic instructions was RNA. But what came before RNA?
AEG is a minute molecule that can link together to form chains, thus providing a backbone for peptide nucleic acids. It could be the answer according to scientists from the US and Sweden who found the molecule in some of the most primitive organisms on Earth – cyanobacteria (bacteria obtaining their energy through photosynthesis). This discovery was unexpected as AEG has never been discovered in living organisms before, and has only ever been synthesised in the pharmaceutical industry to slow or stop certain genetic diseases. They were able to find AEG produced within cyanobacteria from Guam, Japan, Qatar and the Gobi desert of Mongolia; however at the current time there isn’t enough data at present on AEG and its role within the organism to draw any certain conclusions on its exact role in the genetic makeup of such primitive organisms.
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