Perspective on CRISPR-Cas9 Genome Editing of Genetics

^*Correspondence: Abdul Mohammad, University of Texas Health Science Center, Houston, Texas, USA, Email:

Introduction

With the use of the cutting-edge technology CRISPR-Cas9, scientists studying genetics and medicine can modify, add, or remove specific DNA sequences to alter specific regions of the genome. The scientific community is very interested in this method of genetic manipulation since it is currently the most straightforward, adaptable, and precise. Two essential molecules that modify the DNA make up the CRISPR-Cas9 system. Is Cas9 a name for an enzyme? The two DNA strands are cut by this, acting as a pair of "molecular scissors," at a precise spot in the genome, allowing for the addition or deletion of DNA fragments. The guide RNA strand is a kind of RNA (gRNA). This consists of a 20 base long fragment of pre-designed RNA sequence that is placed into a bigger RNA scaffold.

The pre-designed sequence "guides" Cas9 to the appropriate area of the genome as the scaffold binds to DNA. This guarantees that the Cas9 enzyme makes a cut in the genome at the proper spot. The guide RNA [1-3] is designed to find and bind to a certain DNA sequence. The guide RNA's RNA bases complement the target DNA sequence's RNA bases in the genome. As a result, the guide RNA should, in principle, only attach to the target sequence and not to any other parts of the genome.

About the Study

Some bacteria have a CRISPR-Cas9-like gene editing mechanism built within them that they employ to fight off invading diseases like viruses. Much like an immunological system. In order to assist them identify and defend against the virus the next time it attacks, the bacteria utilise CRISPR to cut off portions of the virus DNA and store a piece of it. Some bacteria have a built-in gene editing mechanism, comparable to the CRISPR-Cas9 system that they employ to combat diseases like viruses that are invading their territory. The bacteria utilise CRISPR, which functions similarly to an immune system, to cut out portions of the virus' DNA and save one of those pieces so they can recognise and fight the virus the next time it assaults. Scientists changed this approach so that it could be used to cells from mice and humans as well as other animal species. A number of genetically based medical disorders, including cancer, hepatitis B, and even high cholesterol, may be treated with CRISPRCas9 [4,5]. While there has been much interest in and discussion regarding the idea of editing germline (reproductive) cells, many of the proposed applications involve changing the genomes of somatic (non-reproductive) cells.

Changes made to germline cells have substantial ethical ramifications because they are carried down from generation to generation. The majority of nations, including the UK, now forbid gene editing in germline cells. On the other hand, there is no debate over the use of CRISPR-Cas9 and other gene editing tools in somatic cells. In a few rare and/or serious cases, they have already been employed to treat human disease. Before CRISPR-Cas9 is regularly employed in people, it will probably take years. With the ultimate objective of regularly using the technology to treat diseases in humans, much research is still concentrated on its usage in isolated human cells or animal models. Many efforts are being made to get rid of "off-target" effects, which happen when the CRISPR-Cas9 system edits a different gene than what is intended. The guide RNA typically consists of a particular 20-base sequence.

Conclusion

These are compatible with the target sequence in the gene that may be edited. The guide RNA can bind even when only some of the 20 bases are the same. This presents a challenge since a sequence having, for example, 19 of the 20 complimentary nucleotides might exist in a separate part of the genome. This implies that the target sequence may not bind there or may bind there together with the guide RNA. The wrong mutation will then be introduced since the Cas9 enzyme made a cut at the wrong spot. Even while this mutation might not harm the person, it might have an impact on a crucial gene or another significant portion of the genome.

References

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