CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is basically associated with protein 9 nucleus (Cas9) is a genomic tool which has enabled scientist to edit the parts of a genome sequence by cutting it out, replacing as well as adding parts to a DNA sequence. It is currently the most versatile, simplest and precise method for genetic manipulation and has been creating a buzz in the world of science. Research teams and scientist are very keen on finding a way which ensures that CRISPR-Cas9 would bind and cut accurately.
These are two ways that can help to achieve it:
1. The use of Cas9 enzyme that will only cut a single strand of targeted DNA rather than the double strand. That means the two Cas9 enzyme and the two guide RNAs has to be in the same place for cutting to be made. This reduces the probability of cut being made in a wrong place.
2. The design of more specific guide RNAs by using the knowledge of DNA sequences of the genome and off target behaviors of many versions of Cas9-gRNA complex helps to ensure it binds correctly.
What are the applications of CRISPR?
It has a lot of potential as a tool for the treatment of the range of medical conditions which have a genetic component which include cancer, high cholesterol, and hepatitis B.
There are applications involving editing of the genomes of somatic ( non-reproductive) cells but there is more potential for editing the germ line also known as reproductive cells.
Since any changes which are made in germ line cells can be passed from one generation to another, this has wider implications, but germ line cells gene editing is yet to be been legalized in many countries including UK etc. Some groups have taken advantages from this method to introduce single point mutation in a particular targeted gene with the help of single gRNA.
One of the recent developments is the use of this technique to target protein domains for transcriptional regulations, microscopic visualization of specific loci etc.
CRISPR/Cas9 has enabled rapid genome-wide interrogation of gene function by generating large gRNA library for genomic screening.
Where is the future of CRISPR Cas9 going? And what are the expectations regarding it.
Some of them are listed below:
- One thing for sure, in the future, this technology will be used routinely in human beings
- Although the research is only focused on animal models or isolated human cells, there are possibilities that CRISPR will be used for the treatment of human diseases.
- There is a lot of focus on elimination of “off- target” effects in which this technology cuts in different genes to one which is intended to be edited.