Context: The Nobel Prize in Chemistry for 2020 was announced recently, has two women scientists as its recipients.
About the discovery:
- The two scientists namely Emmanuelle Charpentier and Jennifer A. Doudna, have pioneered the use of CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) – Cas9 (CRISPR-associated protein 9) system as a gene-editing tool.
- Charpentier and Doudna were working independently and later came together to develop this technology of gene editing.
- Their achievement has been recognised through several prestigious awards in the last few years, including the Breakthrough Prize in Life Sciences in 2015 and the Wolf Prize in Medicine, 2020.
- Virginijus Siksnys is also widely recognised as a co-inventor of this technology.
- Siksnys shared the 2018 Kavli Prize in Nanoscience with Doudna and Chapentier for this technology.
Applications of CRISPR: Anything that is linked with functioning of the genes can be corrected, or ‘edited’.
- Eliminate genetic and other diseases : There diseases and disorders, including some forms of cancer, that are caused by an undesired genetic mutation.
- Genetic sequences of disease-causing organisms can be altered to make them ineffective.
- Multiply agricultural production: Genes of plants can be edited to make them withstand pests, or improve their tolerance to drought or temperature.
- It has been happening particularly in the field of agriculture, where several crops have been genetically modified to provide particular traits.
- correct deformities,
- producing ‘designer babies’
- bringing cosmetic perfection.
CRISPR- Cas System:
- It is a technology for gene-editing which replicates a natural defence mechanism in some bacteria that uses a similar method to protect itself from virus attacks.
- An RNA molecule is programmed to locate the particular problematic sequence on the DNA strand.
- A special protein called Cas9, also known as ‘genetic scissor’, is used to break and remove the problematic sequence.
- Because the entire process is programmable, CRISPR has made gene editing very simple and extremely efficient.
- CRISPR(clustered regularly interspaced short palindromic repeats) is a family of DNA sequences found in the genomes of prokaryotic organisms.
- (A prokaryote is a unicellular organism that lacks a membrane-bound nucleus, mitochondria, or any other membrane-bound organelles) such as bacteria and archaea.
- These sequences are derived from DNA fragments of bacteriophages that had previously infected the prokaryote.
- A bacteriophage is a virus that infects and replicates within bacteria and archaea.
- The CRISPR-Cas system is a prokaryotic immune system that confers resistance to foreign genetic elements such as those present within plasmids and phages that provides a form of acquired immunity.
- RNA harboring the spacer sequence helps Cas (CRISPR-associated proteins) recognize and cut foreign pathogenic DNA.
- The technology holds promise in improving the quality of life but there are dangers of its misuse.
- A Chinese researcher recently claimed to produce ‘designer babies’ using the new gene-editing tools like CRISPR.
- In the case of the Chinese twins, the genes were edited to ensure that they do not get infected with HIV, the virus that causes AIDS.
- Issues with producing babies with particular genetic traits
- Potential infection to HIV virus already had other alternative solutions and treatments.
- The gene-editing was done without any regulatory permission or oversight.
- While CRISPR technology is not 100 percent accurate, and it is possible that some other genes could also get altered by mistake.
- Following a global outcry, the WHO formed a panel of gene-editing experts which said “a central registry of all human genome editing research was needed in order to create an open and transparent database of ongoing work.
Scenario in India
- In India, there is a long way to go before realizing the utility of gene editing for therapeutic applications.
- Regulation of genetically modified organisms
- In India, several rules backed by the “Rules for the Manufacture, Use, Import, Export and Storage of Hazardous Microorganisms/Genetically Engineered Organisms or Cells, 1989” notified under the Environment Protection Act, 1986, regulate genetically modified organisms.
- No specific mention of the term gene editing
- The Environment Protection Act, 1986 and the National Ethical Guidelines for Biomedical and Health Research involving human participants, 2017, and the Biomedical and Health Research Regulation Bill implies regulation of the gene-editing process.
- However, currently there is no explicit mention of the term gene editing.
It is time that India came up with a specific law to ban germline editing and put out guidelines for conducting gene-editing research giving rise to modified organisms.
Image Source: TH