Until recently, genomics was a ”read-only” science. But scientists led by Rory Johnson at the Centre for Genomic Regulation in Barcelona and the University of Bern, have now developed a tool for quick and easy deletion of DNA in living cells. This software will boost efforts to understand the vast regions of non-coding DNA, or ”Dark Matter”, in our DNA and may lead to discovery of new disease-causing genes and potential new drugs.
Genomics is the field of research studying how our genome, or entire DNA sequence, specifies a human being, and how errors in this sequence give rise to diseases. Genomics was recently a ”read-only” endeavour: researchers used powerful technology to read genomes’ sequences and their regulatory layers. However, until recently, there was no way to edit or delete DNA for either basic research objectives or for potential therapeutic interventions.
Just a few years ago, this outlook changed dramatically with the discovery of a revolutionary technique for editing genomes: ”CRISPR-Cas9”. CRISPR-Cas9 is a molecular tool composed of two simple components: a molecular barcode, called ”sgRNA”, which is designed by the researcher to recognise one precise location in the genome; and a protein, Cas9, that binds to a structured loop in the sgRNA. By introducing these two units, researchers may perform a wide range of operations on specific pieces of genomic DNA, from introducing small mutations, to regulating gene activity, to tagging it with small sequences. Until recently most studies employing CRISPR-Cas9 were aimed at silencing protein-coding genes, the best-studied part of our genome.
However, our genome consists of 99% of DNA that does not encode any protein. Often described as the ”Dark Matter” of the genome, this non-coding DNA is recognised to be crucially important for understanding all aspects of human biology, including disease and evolution. Until recently, the experimental tools to study this have not been available.
Researchers studying non-coding DNA have been particularly excited about the discovery of CRISPR-Cas9 because it can be used as a powerful tool for studying non-coding DNA for the first time. Prof Rory Johnson, former Staff Scientist at the Computational Biology of RNA Processing laboratory of the Centre for Genomic Regulation (CRG) in Barcelona, Spain and now group leader at the National Center of Competence in Research (NCCR) RNA&Disease and Department of Clinical Research of the University of Bern, recently created a tool based on CRISPR-Cas9, called ”DECKO”, which can be used to delete any desired piece of non-coding DNA. The unique advantage of DECKO is that it uses two individual sgRNAs, acting like two molecular scissors that snip out a piece of DNA. Numerous researchers worldwide have adopted this approach, attracted by its simplicity and effectiveness.
Full article on the CRG website.