The CRISPR-Cas approach is a biotechnological technique that provides a fast mechanism to manipulate single genes in cells. Through this process genes can be precisely deleted, replaced or modified. It is also possible to increase or decrease the activity of individual genes, simultaneously and systematically.
For these reasons CRISPR has become the global standard for biological research as well as in applied fields like plant breeding and, more controversially, embryo research.
What is CRISPR?
CRISPR is an acronym for ‘clustered regularly-interspaced short palindromic repeats. As Digital Journal has reported (see the article: “Is CRISPR technology set to change biological science?”) the technology is a form of biological cut-and-paste molecular scissors. This methods enables researchers to, for example, detect a gene defect within living cells and then make genetic adjustments, such as deleting the gene; repairing it; or completely replacing it.
With the ‘Cas’ aspect, an enzyme called Cas9 functions as the ‘molecular scissors’, capable of slicing two strands of DNA at a specific location in the genome. This happens through the delivery of the Cas9 nuclease complex with a synthetic guide RNA into a cell.
The technology derives from bacteria, where it was discovered that some bacteria, such as Escherichia coli, possess a similar, built-in, gene editing system to CRISPR-Cas9. Bacteria use this mechanism to respond to invading pathogens, such as viruses.
READ MORE: CRISPR could treat rare brain disorder in unborn babies
CRISPR applications
CRISPR is being used by scientists is many remarkable ways. One area is with cancer, where British researchers are deploying the technique to examine the biology of cancerous brain tumors. This research has the objective of producing specialist treatment.
Another area is with coming up with an antimicrobial that forces invasive bacteria ‘commit suicide’. This makes use of Cas to chop up the genes of an invading bacterium and then using a CRISPR laced bacteriophage to infect bacteria and insert viral material into the pathogen cell.
A third area is with agriculture. An example comes from Tokushima University where scientists have developed seedless tomatoes using CRISPR. This type of fruit could be a key contributor towards more sustainable food production, being able to be produced scratch in laboratories. By being laboratory grown this overcome environmental variants like pollination, rain or sunlight, which could reduce crop yields.
The following short video explains more about CRISPR technology:
New developments
A limitation with CRISPR is that researchers can only modify one gene at a time using the technique. With the new advance, the Swiss research group has developed a new process that can modify up to 25 target sites within genes in a cell simultaneously.
Going forward it seems that the number of genes can that be modified could increase to dozens or even hundreds of genes. This development has the potential to push ahead advanced with biomedical research.
According to lead researcher Professor Randall Platt: “Thanks to this new tool, we and other scientists can now achieve what we could only dream of doing in the past.”
He adds: “Our method enables us, for the first time, to systematically modify entire gene networks in a single step.”
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Using the new method
The modification to the CRISPR method has a number of potentially useful applications. These include investigating why different types of cells behave differently or to delve deep into complex genetic disorders. The technology should also assist with cell replacement therapy, where damaged are replaced with healthy cells.
Research paper
The research has been published in the journal Nature Methods. The research paper is titled “Multiplexed genome engineering by Cas12a and CRISPR arrays encoded on single transcripts.”
Essential Science
This article is part of Digital Journal’s regular Essential Science columns. Each week Tim Sandle explores a topical and important scientific issue. Last week we learned how scientists have fitted a wireless device to the brains of mice and can control the brain neurons via smartphone. It may have an ominous, dystopian sci-fi feel to it but there is a serious side too, with potential for healthcare.
The week before we learned about a large cloud of radioactive material that hovered over most of Europe for a few days, and reviewed research that pinpointed its probable origin.
