QUESTION : What do you understand by CRISPR Cas9 editing technology? Recently there have been growing ethical concerns regarding the genome editing technology. Discuss.
GENE EDITING,THE GOOD FIRST AND THEN THE WORRIES
WHAT ?
The Nobel Prize in Chemistry for 2020
WHY IN NEWS ?
The recently announced Nobel Prize in Chemistry for 2020 has two women scientists as its recipients. Emmanuelle Charpentier, microbiologist and Jennifer Doudna, a biochemist shared the honour for the development of a method for genome editing.
ABOUT THE DISCOVERY :
- The two scientists have pioneered the use of CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) – Cas9 (CRISPR-associated protein 9) system as a gene-editing tool.
- In a short period of eight years since its discovery, the method has already made a significant impact in biology, medicine, and agriculture.
- It is not often that one sees practical applications of scientific findings in such a short time. The only other work with such a quick and revolutionary impact, is PCR (polymerase chain reaction) invented by Kary Mullis in 1983.
- The Nobel committee recognised Charpentier and Doudna as the sole discovers for programming a Cas9 protein to cut a piece of DNA at a specific site with the help of a small piece of RNA, thereby proving the ability of CRISPR-Cas9 to function as a gene-editing tool
WHAT IS GENE EDITING ?
- Genome editing (also called gene editing) is a group of technologies that give scientists the ability to change an organism’s DNA (Deoxyribonucleic acid).
- These technologies allow genetic material to be added, removed, or altered at particular locations in the genome. Several approaches to genome editing have been developed.
- There are currently three powerful Gene editing technologies:
Zinc-finger nucleases (ZFNs), Transcription activator-like effector nucleases (TALENs) and CRISPR-Case9 Technology.
- There are two different types of gene editing technology depending on which types of cells are treated:
- Somatic gene therapy: transfer of a section of DNA to any cell of the body that doesn’t produce sperm or eggs. Effects of gene therapy will not be passed onto the patient’s children.
- Germline gene therapy: transfer of a section of DNA to cells that produce eggs or sperm. Effects of gene therapy will be passed onto the patient’s children and subsequent generations
WHAT IS CRISPR-Cas9 ?
- It is a Gene editing technique which is short for Clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9.
- The CRISPR-Cas9 gene editing tool has two components — a short RNA (Ribonucleic acid) sequence that can bind to a specific target of the DNA and the Cas9 enzyme which acts like a molecular scissor to cut the DNA.
- To edit a gene of interest, the short RNA sequence (gRNA) that perfectly matches with the DNA sequence that has to be edited is introduced.
- Once it binds to the DNA, the Cas9 enzyme cuts the DNA (like scissors) at the targeted location where the RNA sequence is bound. Once the DNA is cut, the natural DNA repair mechanism is utilised to add or remove genetic material or make changes to the DNA.
ETHICAL CONCERN :
- 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
o Potential infection to HIV virus already had other alternative solutions and treatments.
o 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.
SIGNIFICANCE :
- In the last six years, the tool has enabled scientists to edit human DNA in a dish and early-stage clinical trials are being attempted to use the tool to treat a few diseases, including inherited disorders/diseases and some types of cancer.
- In the male-dominated world of science, this year’s Nobel chemistry prize should be widely celebrated worldwide.
- The recognition that Charpentier and Doudna’s work has received will encourage women to take up science as a career, despite the hard struggle to balance family life and an arduous life in a scientific career.
- The CRISPR technology can detect specific sequences of DNA within a gene and uses an enzyme functioning as molecular scissors to snip it.
- It also allows researchers to easily alter DNA sequences and modify gene function.
- The technology can also be configured for detection of multiple other pathogens in the future.
- Unlike in the case of humans, the tool is being extensively used in agriculture. It is being tried out in agriculture primarily to increase plant yield, quality, disease resistance, herbicide resistance and domestication of wild species.
- The huge potential to edit genes using this tool has been used to create a large number of crop varieties with improved agronomic performance; it has also brought in sweeping changes to breeding technologies.
SITUATION IN INDIA :
- In India, several rules, guidelines, and policies 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.
- The above Act and the National Ethical Guidelines for Biomedical and Health Research involving human participants, 2017, by the Indian Council of Medical Research (ICMR), and the Biomedical and Health Research Regulation Bill implies regulation of the gene-editing process.
- This is especially so in the usage of its language modification, deletion or removal of parts of heritable material. However, 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.
WAY FORWARD :
- Experts recommend that germline editing should be done only on genes that lead to serious diseases and when no other reasonable treatment alternatives exist.
- Among other criteria, they stress the need to have data on the health risks and benefits and the need for continuous oversight during clinical trials. They also recommend following up on families for multiple generations.
- CRISPR technology is indeed a path-breaking technology, to alter genes in order to tackle a number of conventional and unconventional problems. The most promising use of the CRISPR technology is in treatment of diseases. For example, sickle cell anaemia.
- However, experiments and tests to validate its use must be subjected to appropriate scrutiny by the regulators, and their use must be controlled to prevent commercial misuse.
- Scientists across the world are still working to determine whether the CRISPR technology is safe and effective for use in people.
CONCLUSION :
India should come up with a specific law to ban germline editing and put out guidelines for conducting gene-editing research giving rise to modified organisms.
QUESTION : What are the reasons and costs of rising air pollution in Delhi? Enumerate the measures taken by government in this direction .
TOWARDS CLEANER AIR IN DELHI
WHAT ?
Air Pollution
WHY IN NEWS ?
The launching of an anti-pollution campaign by the Delhi administration.
ANTI-POLLUTION CAMPAIGN IN DELHI :
- With air pollution returning to pre-COVID levels, the Delhi administration has launched a major anti-pollution campaign this month.
- The campaign is focused on cutting the deadly smoke from thermal plants and brick kilns in the National Capital Region as well as on chemical treatment of stubble burning from nearby States.
REASONS FOR AIR POLLUTION IN DELHI :
Stubble Burning: Stubble burning in Punjab, Rajasthan and Haryana is blamed for causing a thick blanket of smog in Delhi during winters.
o It emits large amounts of toxic pollutants in the atmosphere which contain harmful gases like Methane (CH4), Carbon Monoxide (CO), Volatile organic compounds (VOC) and carcinogenic polycyclic aromatic hydrocarbons.
Vehicular Emission: The Central Pollution Control Board (CPCB) and the National Environmental Engineering Research Institute (NEERI) have declared vehicular emission as a major contributor to Delhi’s increasing air pollution.
o Vehicles contribute 40% of the total pollution load in the city.
Topography: Delhi lies in landlocked Indo-Gangetic region which does not have a geographical advantage that eastern, western or southern parts of the country enjoy.
o There is no sea breeze to disperse the concentrated pollutants.
Construction Sector: Large scale construction in Delhi-NCR is another culprit that is increasing dust and pollution in the air.
Fire Crackers: Despite the ban on cracker sales, firecrackers were a common sight this Diwali. It may not be the top reason for air pollution, but it definitely contributed to its build up.
Dust Storm from Gulf countries: During the smog in the year 2017, the dust storm from Gulf countries was also the reason which enhanced already worse condition.
REDUCING EMISSION FROM TRANSPORTATION :
- Delhi’s long-term solution will depend importantly also on abating emissions from transportation.
- Delhi needs a 65% reduction to meet the national standards for PM2.5.
- Vehicles, including trucks and two-wheelers, contribute 20%-40% of the PM2.5 concentrations.
- Tackling vehicle emissions would be one part of the agenda, as in comparable situations in Bangkok, Beijing, and Mexico City.
PLAN OF ACTION COMBATING EMISSIONS :
A three-part action comprises emissions standards, public transport, and electric vehicles.
1) Stricter enforcement of emission controls
- Two-wheelers and three-wheelers were as important as cars and lorries in Beijing’s experience.
- Bangkok ramped up inspection and maintenance to cut emissions.
- The first order of business is to implement the national standards.
2) Strengthening public transport
- Bus Rapid Transit (BRT) around the world show how the sizeable investment cost is more than offset by the benefits, and that financing pays off.
- Delhi has lessons from its BRT experience in designating better BRT lanes, improving the ticketing system and synchronising with the Metro.
- The Supreme Court’s ruling to increase Delhi’s bus fleet and align it with the Metro network must be carried out.
- The ‘odd-even’ number plate policy can help, but the system should reduce exemptions, allow a longer implementation period, and complement it with other measures.
3) Adoption of electric vehicle: A long term solution
- Subsidies and investment will be needed to ensure that EVs are used to a meaningful scale.
- The Delhi government’s three-year policy aims to make EVs account for a quarter of the new vehicles registered in the capital by 2024.
- EVs will gain from purchase incentives, scrappage benefits on older vehicles, loans at favourable interest and a waiver of road taxes.
NEED FOR COORDINATION AT VARIOUS LEVEL :
- Transport solutions need to be one part of pollution abatement that includes industry and agriculture.
- Delhi’s own actions will not work if the pollution from neighbouring States is not addressed head on.
- Technical solutions need to be underpinned by coordination and transparency across Central, State, and local governments.
- Public opinion matters.
- Citizen participation and the media are vital for sharing the message on pollution and health, using data such as those from the Central Pollution Control Board.
GOVT INITIATIVES TACKLING AIR POLLUTION :
Notification of National Ambient Air Quality Standards and sector-specific emission and effluent standards for industries;
Setting up of monitoring network for assessment of ambient air quality;
Introduction of cleaner gaseous fuels like CNG, LPG etc and ethanol blending;
Launching of National Air Quality Index (AQI);
Leapfrogging from BS-IV to BS-VI standards for vehicles by 1st April 2020;
Banning of burning of biomass;
Promotion of public transport network;
Pollution Under Control Certificate;
Issuance of directions under Air (Prevention and Control of Pollution) Act, 1981;
Installation of on-line continuous (24×7) monitoring devices by 17 highly polluting industrial sectors;
Regulating the bursting of pollution-emitting crackers;
Notification of graded response action plan for Delhi identifying source wise actions for various levels of air pollution, etc.
Even – Odd formula.
CONCLUSION :
It is a matter of prioritising people’s health and a brighter future. Once the pandemic is over, Delhi must not stumble into yet another public health emergency.
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