CRISPR / Gene Editing
Subject- Science and Technology
Source- The Hindu
- Recently, the gene-editing technology which has led to innovations in medicine, evolution and agriculture has completed 10 years of innovation.
About Gene Editing
- A decade ago, scientists in Germany and the US discovered a technique which allowed them to ‘cut’ DNA strands and edit genes.
- Gene/genome editing refers to technology that permits to change an organism’s DNA.
- These technologies allow genetic material to be added, removed, or altered at particular locations in the genome.
- Its applications include correcting genetic defects, treating and preventing the spread of diseases and improving crops etc.
- Advanced research has allowed scientists to develop the highly effective clustered regularly interspaced palindromic repeat (CRISPR) -associated proteins-based systems.
- This system allows for targeted intervention at the genome sequence.
- This tool has opened up various possibilities in plant breeding. Using this tool, agricultural scientists can now edit the genome to insert specific traits in the gene sequence.
- Depending on the nature of the edit that is carried out, the process is divided into three categories — SDN 1, SDN 2 and SDN 3.
- SDN1 introduces changes in the host genome’s DNA through small insertions/deletions without introduction of foreign genetic material.
- In the case of SDN 2, the edit involves using a small DNA template to generate specific changes.
- The SDN3 process involves larger DNA elements or full length genes of foreign origin which makes it similar to genetically modified organisms (GMO) development.
- Researchers have been able to modify the genomes of specific tissues such as liver and brain tissues using hydrodynamic injection and adeno-associated virus (AAV).
- CRISPR-Cas9 can be used to generate mutants for target genes.
- CRISPR-Cas9 can be used to create animal models to mimic human diseases and to understand disease development by mutating or silencing genes.
- CRISPR-Cas9 can be applied to cells in vivo or ex vivo. In the in vivo approach, CRISPR-Cas9 is directly transferred to cells in the body using either viral or nonviral methods. In the ex vivo approach, first the cells are removed from the body; then CRISPR is applied to the cells and they are transferred back to the body.
- CRISPR was first used for commercial purposes to make bacterial cultures used in cheese and yoghurt production resistant to viral infections.
- Single-stranded RNA (ssRNA) sequences can also be edited by CRISPR-Cas9.
- These studies are commonly focused on increasing the tolerance of soldiers against biological or chemical warfare. This technology has the potential to influence human performance optimization.