To some it sounds like something out of a spy story – sub-codes within the genetic code. Ah the hidden code; Dan Brown would be proud of the discovery. The actual discovery is perhaps not so thrilling, but potentially much more important than novelistic entertainment. Two researchers, Professor Yves Barral (ETH Zurich, Switzerland), and Dr. Gina Cannarozzi (Swiss Institute of Bioinformatics, Switzerland) used advanced computer modeling techniques to tease out of the DNA coding sequences (codons) the existence of sub-codes that play a role in controlling the expression of genes. It’s not like these sub-sequences were hidden, it’s just that geneticists didn’t know what they did. Now that the link between these sub-codes and the expression of genes has been made, it adds to the storehouse of knowledge about how DNA works – and opens a new chapter in the study of the way DNA information has evolved into a compacted format to support different parts of the genetic process.
The existence of sub-coding within the DNA sequences has been known for some time. DNA (deoxyribonucleic acid) contains the ‘code of life’ – the genes that dictate what proteins are synthesized for the construction of body cells, tissues, organs, and their function. Within the vast sequences of genetic instruction (codons) there is a lot of material that has not been linked to specific genes or explained for any particular function. Some of this used to be called ‘junk DNA.’ These days, as more and more of the DNA structure is analyzed, scientists discover that DNA uses many different sequences, often in combination with ‘feedback’ information provided by cellular genetics (various forms of RNA), to not only provide the blueprint for protein production, but also to regulate and direct that production. The discovery of genetic sub-codes fits into this general analysis of DNA.
The sub-code discovered by Barral and Cannarozzi appears to have influence on the rate at which certain proteins are constructed. There are many situations when cells must react quickly to physical or chemical damage. In such situations, prioritization – in the form of controlling which genes are expressed and how fast – is a helpful mechanism. That’s what the sub-code appears to do. By reading this code, it is possible to discern which genes will be turned on quickly, and which will be turned on more slowly.
This same information could be gleaned by laboriously analyzing the molecular/chemical results of cell reaction to trauma; but reading it directly from DNA is much more efficient. It also may provide a way to use the information to intervene in the control functionality – although this is, at this point, highly speculative (and way down the road). The researchers found a potential approach to using sub-codes in their role of producing transcription RNA (tRNA – the principle controller molecule that translates the DNA blueprint into protein).