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The segments of DNA called 'CRISPR' whose special characteristics include short repetitions of base sequences, has been used mostly for genome editing till date. For the first time, a team of researchers from the University of Massachusetts Medical School have used CRISPR for labelling DNA and tracking the movement of DNA in live cells. In a newly published research work, the scientists working on the project, have presented a new technology called 'CRISPRainbow' that now lets them tag & track 7 different locations of genome inside living cells.With the new advancement that lets scientists determine the exact location of these genomic elements, it is now possible to better understand chromosome dynamics. It so happens that knowing the location of a genome in the 3D space inside a live cell helps in finding which genes control human biology and health. This information is crucial for studying applications such as embryonic development and cancer.Using the currently available technologies, scientists could only track at the most 3 genomic locations in live cells. If they tried to go any further, the cells needed to be fixed by putting them in formaldehyde (CH2O - methanal) - the organic compound that would actually kill the cell and make it impossible for them to observe the structural changes in chromosome over a period of time.To solve this impending problem, the Massachusetts researchers create a Cas9 mutation that will only bind to the DNA and not cut the genome. Upon deactivation, the CRISPR/Cas9 element is guided to a location on the genome by a pre-programmed RNA. For tracking the CRISPR/Cas9 complex once it has been bound to the genome, they made the RNA include one of three primary fluorescent proteins - red, green or blue.It was now possible to study and track these proteins under a microscope in real time. The researchers further attached a second fluorescent protein to the guide RNA to create three additional labels: cyan, magenta and yellow and by making a combination of 3 primary colors, a seventh label - white was created as well.Since there are 7 different locations that the scientists can now track, the technology is being called 'CRISPRainbow'. This system is advanced enough to even track the topological movements of the genome, a study that could help in researching various biological consequences. Now the scientists can not only find out the location of the genome, but also check how far and fast these loci move.Real time movement tracking of genomes inside living cells can prove to be a real benefit for the medical researchers to study human health and diseases. It's a step ahead in the game. Check out the following video to hear what the researchers have to say:Source: University of Massachusetts