CRISPR gene editing
CRISPR gene editing is a genetic engineering technique in molecular biology. It is based on a simplified version of the bacterial CRISPR-Cas9 antiviral defense system. By delivering the Cas9 nuclease complexed with a synthetic guide RNA into a cell, the cell’s genome can be cut at a desired location. The development of the technique earned Jennifer Doudna and Emmanuelle Charpentier the Nobel Prize in Chemistry in 2020.
About CRISPR gene editing in brief
CRISPR gene editing is a genetic engineering technique in molecular biology. It is based on a simplified version of the bacterial CRISPR-Cas9 antiviral defense system. By delivering the Cas9 nuclease complexed with a synthetic guide RNA into a cell, the cell’s genome can be cut at a desired location. The technique is considered highly significant in biotechnology and medicine. It can be used in the creation of new medicines, agricultural products, and genetically modified organisms. It also has possibilities in the treatment of inherited genetic diseases as well as diseases arising from somatic mutations such as cancer. The development of the technique earned Jennifer Doudna and Emmanuelle Charpentier the Nobel Prize in Chemistry in 2020. Many bioethical concerns have been raised about the prospect of using CRISpr for germline editing, especially in human embryos. The use of the CRisPR-cas9-gRNA complex for genome editing was the AAAS’s choice for Breakthrough of the Year in 2015. The ease with which researchers can insert Cas9 and template RNA in order to silence or cause point mutations at specific loci has proved invaluable to the quick and efficient mapping of genomic models and biological processes associated with various genes in a variety of eukaryotes. In the early 2000s, Sangamo researchers began developing zinc finger nucleases (ZFNs) whose DNA-binding domains enable them to create double-stranded breaks in DNA at specific points. ZFNs have a higher precision and the advantage of being smaller than Cas9, but they are not as commonly used as CRIS PR-based methods.
In 2010, transcriptionator-like effector nucleases provided an easier way to target a specific double- Stranded break on the DNA strand. Both zinc fingerucleases and TALs require the design and creation of a custom DNA sequence for each targeted DNA sequence, which is a much more difficult and time-consuming process than that of designing guide RNAs. As a result of this, the precision of genome edited is a great concern. Genomic editing leads to irreversible changes to the genome. With the discovery of CR ISPR and specifically the Cas 9 nucleasing molecule, efficient and highly selective editing is now a reality. Newly engineered variants of Cas9 have been developed that significantly reduce off-target activity, which significantly reduce the risk of DNA damage at the target site. The Cas9 Nuclease can also provide several different target sites simultaneously by introducing several different DNA gRNAs simultaneously. This allows for the introduction of targeted DNA damage and repair at a specific location as designated by the crRNA and tracrRNA guide strands. It has many potential applications, including in medicine and agriculture. However, its use in human germline genetic modification is highly controversial. It does not fully suppress gene function, and does not do fully suppress genes as fully as other techniques such as TALENs, ZFN, and TENEN do.