This question masquerades as Current Affairs but is actually a 'Definition Logic' test. If you understand that RNAi is a 'silencing' mechanism (it destroys mRNA), you can logically deduce it cannot be used for 'Hormone Replacement' (which requires creating/adding proteins). The source is general science news, but the solution lies in basic biological concepts.
How this question is built
This question can be broken into the following sub-statements.
Tap a statement sentence to jump into its detailed analysis.
Statement 1
Can RNA interference (RNAi) be used in developing gene-silencing therapies?
Origin: Web / Current Affairs
Fairness: CA heavy
Web-answerable
"RNA interference (RNAi) is a gene-silencing technology with great potential in cancer therapy"
Why this source?
- Explicitly names RNAi as a gene-silencing technology applicable to therapy.
- Specifically cites its potential in cancer therapy, showing practical therapeutic use.
"silencing by siRNA, and RNA interference (RNAi) has the potential to be used in the treatment of genetic diseases and cancer."
Why this source?
- States RNAi (siRNA) has potential to be used in treatment of genetic diseases and cancer.
- Provides an example where siRNA delivered by biomimetic nanoparticles enabled gene silencing in lungs.
"RNA interference (RNAi) is a significant biological mechanism in which the existence of double-stranded RNA (dsRNA) inhibits the specific gene expressions with a homologous sequence to the dsRNA."
Why this source?
- Describes the RNAi mechanism (dsRNA inhibits specific gene expression), explaining how gene silencing is achieved.
- Mentions siRNAs and miRNAs as the molecular agents used in RNAi, supporting feasibility for therapeutic application.
Science , class X (NCERT 2025 ed.) > Chapter 8: Heredity > 8.2.3 How do these Traits get Expressed? > p. 131
Strength: 5/5
“If this enzyme works efficiently, a lot of hormone will be made, and the plant will be tall. If the gene for that enzyme has an alteration that makes the enzyme less efficient, the amount of hormone will be less, and the plant will be short. Thus, genes control characteristics, or traits. If the interpretations of Mendelian experiments we have been discussing are correct, then both parents must be contributing equally to the DNA of the progeny during sexual reproduction. We have disscussed this issue in the previous Chapter. If both parents can help determine the trait in the progeny, both parents must be contributing a copy of the same gene.”
Why relevant
States that genes control characteristics/traits and that changes in gene function alter phenotype.
How to extend
A student could infer that deliberately reducing a gene's activity (via RNAi) could alter a trait or disease-related function and so might be therapeutic.
Indian Economy, Nitin Singhania .(ed 2nd 2021-22) > Chapter 9: Agriculture > GENETICALLY MODIFIED (GM) CROPS > p. 301
Strength: 4/5
“• According to WHO, Genetically Modified Organisms (GMO) are the plants, animals or microorganisms in which the hereditary material (DNA) is altered in a manner that does not happen normally by mating or potentially regular recombination. It is also known as modern biotechnology/gene technology.• When genetic modification of a plant is performed, foreign gene (transgene) or gene of some other organism is artificially inserted into the plant's own genes. This is gene modification.”
Why relevant
Defines genetic modification as altering hereditary material by inserting foreign genes, showing that molecular alteration of genes is a recognized intervention.
How to extend
Combine this idea with knowledge of RNAi as a method to modify gene expression (without inserting transgenes) to judge feasibility of gene-silencing therapies.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 16: Conservation Efforts > 16.17. DNA BARCODING > p. 248
Strength: 4/5
“A MoU signed between Zoological Survey of India (ZSI), a subordinate organization under MoEF&CC, and International Barcode of Life (iBOL), a Canadian not-for-profit corporation. ZSI and iBOL have come together for further efforts in DNA barcoding, a methodology for rapidly and accurately identifying species by sequencing a short segment of standardized gene regions and comparing individual sequences to a reference database. iBOL is a research alliance involving nations that have committed both human and financial resources to enable expansion of the global reference database, the development of informatics platforms, and/or the analytical protocols needed to use the reference library to inventory, assess, and describe biodiversity.”
Why relevant
Describes DNA sequencing/ barcoding as a method to identify standardized gene regions and build reference databases.
How to extend
A student could reason that sequencing allows precise identification of target genes/transcripts, a prerequisite for designing specific RNAi therapeutics.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 16: Conservation Efforts > Goals: > p. 249
Strength: 3/5
“• Deliver DNA barcoding technology for 5 million species. • Develop the informatics platform and analytical protocols required for the development of a DNA barcode reference library. • Establish a core facility to provide sequencing and informatics support.
• Complete the census of all multicellular species.
• Establish a global biosurveillance program.
• Construct a 'library of life' by preserving DNA extracts from all species.”
Why relevant
Lists goals to develop sequencing, informatics, and analytical protocols and to preserve DNA extracts—indicating capacity for molecular identification and analysis.
How to extend
Use this to support the idea that necessary molecular tools and infrastructure exist to develop targeted gene-silencing agents like RNAi.
Indian Economy, Nitin Singhania .(ed 2nd 2021-22) > Chapter 21: Sustainable Development and Climate Change > BY MINISTRY OF SCIENCE AND TECHNOLOGY > p. 617
Strength: 2/5
“• Technology Development Board under the Department of Science & Technology (DST) has invited proposals from Indian companies and start-ups to fund the development of indigenous technology needed to fight COVID-19. Major areas for which financial support is available are surveillance, laboratory support, infection prevention and control. • Science & Engineering Research Board (SERB) to fund R&D proposals under IRHPA Ø”
Why relevant
Notes funding calls for indigenous technology development and support for R&D under science boards, implying institutional support for biotech solutions.
How to extend
A student could infer that financial and institutional resources may be available to develop RNAi-based therapies if scientifically justified.
Statement 2
Can RNA interference (RNAi) be used to develop therapies for the treatment of cancer?
Origin: Web / Current Affairs
Fairness: CA heavy
Web-answerable
"This article focuses on combinations of siRNA with chemotherapeutic drug delivery systems for the treatment of cancer"
Why this source?
- Directly addresses siRNA-based therapy applied to cancer treatment.
- Identifies the main delivery challenge, implying active research toward therapeutic use.
"RNA interference (RNAi): RNAi technology has the potential to suppress cellular production of certain proteins ... Efforts are being made to develop this tool to target disease-causing genes and proteins that are inaccessible to conventional drugs."
Why this source?
- States RNAi technology can suppress production of specific proteins relevant to therapeutic goals.
- Notes efforts to develop RNAi to target disease-causing genes and proteins inaccessible to conventional drugs.
"Although this was an example of non-cancerous disease, it can provide insights that such failures can happen in the treatment of cancer using RNA therapeutics. The failure of RNA therapy for cancer treatment in patients can stem from a complex interplay of biological, delivery-related, and tumor-specific factors"
Why this source?
- Discusses RNAi/ RNA therapeutics in the context of clinical development and failures, including relevance to cancer.
- Highlights that challenges (biological and delivery-related) can undermine RNA therapy effectiveness in cancer, implying active but difficult therapeutic application.
Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 3: Health: The Ultimate Treasure > Be a scientist > p. 37
Strength: 5/5
“Dr. Kamal Ranadive (1917–2001) was a pioneering biomedical researcher. She studied how hormones and certain viruses are linked to cancer, helping improve its treatment and prevention. Her work also showed how tobacco, diet, and pollution can raise the risk of cancer, highlighting the importance of a healthy lifestyle.”
Why relevant
Describes biomedical research linking hormones and viruses to cancer, showing cancer can have specific molecular causes.
How to extend
A student could combine this with the basic fact that RNAi silences specific genes to reason that if cancer depends on particular genes/pathways, RNAi might be used to target them.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 12: Major Crops and Cropping Patterns in India > Table III Pharmaceutical Plants, Drugs and Use > p. 90
Strength: 4/5
“• Drug: Cocaine; Plant Source: Cocoa; Use: Analgesic and local anesthetic; reduces pain and prevents pain during sur gery. • Drug: Codeine; Plant Source: Opium puppy; Use: Analgesic and local anesthetic; reduces pain. • Drug: Colchicines; Plant Source: Autumn crocus; Use: Anticancer agent • Drug: Digitoxin; Plant Source: Common foxglove; Use: Cardiac stimulant used in heart diseases • Drug: Diosgenin; Plant Source: Wild yams; Use: Source of female contraceptive; prevents pregnancy • Drug: Ergotamine; Plant Source: Smut-of-rye or regot; Use: Control of hemorrhage and migraine headaches • Drug: Glaziovine; Plant Source: Ocotea glaziovii; Use: Antidepressant • Drug: Gossypol; Plant Source: Cotton; Use: Male contraceptive • Drug: Indicine N-oxide; Plant Source: Heliotropium Indi cum Mint; Use: Anticancer agent • Drug: L-Dopa; Plant Source: Velvet bean; Use: Controls Parkinson which leads to jerky movements of the hands • Drug: Menthol; Plant Source: Mint; Use: Rubefacient; increases local blood supply and reduces pain on local ap plications • Drug: Monocrotaline; Plant Source: Cotolaria sessilifora; Use: Anticancer agent • Drug: Papain; Plant Source: Papaya; Use: Dissolves excess protein and mucus, during digestion • Drug: Penicillin; Plant Source: Penicillium fungi; Use: General antibiotic, kills bacteria and controls infection by various micro organisms • Drug: Quinine; Plant Source: Yellow cinchona; Use: Antimalarial • Drug: Reserpine; Plant Source: Indian snakeroot; Use: Reduces high blood pressure • Drug: Scopolamine; Plant Source: Torn apple; Use: Sedative • Drug: Taxol; Plant Source: Pacifc yew; Use: Anticancer (ovarian) • Drug: Vinblastine; Plant Source: Rosy periwinkle; Use: Anticancer agent; controls cancer in children • Drug: Vincristine; Plant Source: (Vinca rosea) (Sadaphali); Use: Anticancer agent; controls cancer in children Source: Wilson, E.O., 1993, Te Diversity of Life, Harvard University Press.”
Why relevant
Lists multiple anticancer agents derived from biological sources, illustrating that molecularly targeted compounds can treat cancer.
How to extend
A student could extend this by noting that therapies can act on molecular targets and therefore explore whether RNAi (a molecular tool) could be used similarly to inhibit cancer-promoting genes.
Contemporary World Politics, Textbook in political science for Class XII (NCERT 2025 ed.) > Chapter 5: Security in the Contemporary World > Security in the Contemporary World 75 > p. 75
Strength: 3/5
“By 2003, an estimated 4 crore people were infected with HIV-AIDS worldwide, two-thirds of them in Africa and half of the rest in South Asia. In North America and other industrialised countries, new drug therapies dramatically lowered the death rate from HIV-AIDS in the late 1990s. But these treatments were too expensive to help poor regions like Africa where it has proved to be a major factor in driving the region backward into deeper poverty. Other new and poorly understood diseases such as Corona, ebola virus, hantavirus, and hepatitis C have emerged, w h i l e o l d d i s e a s e s l i k e tuberculosis, malaria, dengue fever and cholera have mutated into drug resistant forms that are difficult to treat.”
Why relevant
Notes that new drug therapies dramatically lowered disease death rates, demonstrating that novel therapeutic approaches can change cancer/outcome landscapes.
How to extend
A student could infer that development of new modalities (like RNAi-based drugs) is a plausible route to improved cancer therapy and then check feasibility/clinical progress.
Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 3: Health: The Ultimate Treasure > Activity 3.7: Let us infer > p. 42
Strength: 3/5
“and minerals for managing illnesses and promoting recovery, and focus on a healthy lifestyle and balanced diet. While these systems can help with some conditions, and are useful for everyday well-being, they may not be effective for all diseases and at all stages.
Therapies for non-communicable diseases focus on managing symptoms and improving quality of life through medication, lifestyle changes, and rehabilitation. Early diagnosis and continuous care are key to control the disease progression and prevent complications.”
Why relevant
Explains that therapies for non-communicable diseases focus on managing symptoms, early diagnosis and continuous care, implying varied therapeutic strategies are used depending on disease mechanisms.
How to extend
A student could use this to motivate investigating whether RNAi would be suited as a mechanism-based therapy (versus symptomatic) for cancers with identifiable gene drivers.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 19: Ozone Depletion > Effects of human and animal health > p. 271
Strength: 2/5
“• o Potential risks include an increase in the incidence of and morbidity from eye diseases, skin cancer and infectious diseases. • rUV radiation has been shown in experimental ' systems to damage the cornea and lens of the eye. Experiments in animals show that UV exposure decreases the immune response to skin cancers: infectious agents and other antigens and can lead to unresponsiveness upon repeated challenges.
r In susceptible (light-skin coloured) populations, UV-B radiations is the key risk factor for development of non-melanoma skin cancer (NMSC).”
Why relevant
Shows that environmental factors (UV-B) can alter immune responses and contribute to cancer, indicating cancer involves biological pathways amenable to intervention.
How to extend
A student could combine this with the concept of gene/pathway modulation (via RNAi) to consider targeting pathways altered by environmental carcinogens.
Statement 3
Can RNA interference (RNAi) be used to develop hormone replacement therapies?
Origin: Weak / unclear
Fairness: Borderline / guessy
Indirect textbook clues
Science , class X (NCERT 2025 ed.) > Chapter 6: Control and Coordination > Activity 6.2 > p. 108
Strength: 4/5
“If, instead of generating an electrical impulse, stimulated cells release a chemical compound, this compound would diffuse all around the original cell. If other cells around have the means to detect this compound using special molecules on their surfaces, then they would be able to recognise information, and even transmit it. This will be slower, of course, but it can potentially reach all cells of the body, regardless of nervous connections, and it can be done steadily and persistently. These compounds, or hormones used by multicellular organisms for control and coordination show a great deal of diversity, as we would expect.”
Why relevant
Defines hormones as chemical signals released by cells and detected by specific surface molecules, implying therapy could target hormone production or detection pathways.
How to extend
A student could reason that suppressing or boosting genes for hormone synthesis or receptors (via RNAi) might alter these chemical signals and thus mimic or restore hormonal function.
Science , class X (NCERT 2025 ed.) > Chapter 6: Control and Coordination > Do You Know? > p. 110
Strength: 4/5
“Iodine is essential for the synthesis of thyroxin. In case iodine is deficient in our diet, there is a possibility that we might suffer from goitre. One of the symptoms in this disease is a swollen neck. Can you correlate this with the position of the thyroid gland in Fig. 6.7? Sometimes we come across people who are either very short (dwarfs) or extremely tall (giants). Have you ever wondered how this happens? Growth hormone is one of the hormones secreted by the pituitary. As its name indicates, growth hormone regulates growth and development of the body. If there is a deficiency of this hormone in childhood, it leads to dwarfism.”
Why relevant
Gives an example where deficiency of a required element (iodine) reduces a hormone (thyroxin) causing disease, showing hormone levels critically affect physiology.
How to extend
One could infer that correcting hormone levels — possibly by modulating the biosynthetic pathway genes with RNAi or other molecular tools — might treat such deficiencies.
Science , class X (NCERT 2025 ed.) > Chapter 8: Heredity > 8.2.3 How do these Traits get Expressed? > p. 131
Strength: 5/5
“If this enzyme works efficiently, a lot of hormone will be made, and the plant will be tall. If the gene for that enzyme has an alteration that makes the enzyme less efficient, the amount of hormone will be less, and the plant will be short. Thus, genes control characteristics, or traits. If the interpretations of Mendelian experiments we have been discussing are correct, then both parents must be contributing equally to the DNA of the progeny during sexual reproduction. We have disscussed this issue in the previous Chapter. If both parents can help determine the trait in the progeny, both parents must be contributing a copy of the same gene.”
Why relevant
States that genes control enzymes that produce hormones, and that changes in those genes alter hormone amounts and phenotypes.
How to extend
A student might extend this to hypothesize that RNAi, which can reduce expression of specific genes, could be used to lower or fine-tune enzyme levels involved in hormone synthesis as a therapeutic strategy.
Science , class X (NCERT 2025 ed.) > Chapter 7: How do Organisms Reproduce? > 7.3.3 (d) Reproductive Health > p. 125
Strength: 4/5
“These drugs commonly need to be taken orally as pills. However, since they change hormonal balances, they can cause side-effects too. Other contraceptive devices such as the loop or the copper-T are placed in the uterus to prevent pregnancy. Again, they can cause side effects due to irritation of the uterus. If the vas deferens in the male is blocked, sperm transfer will be prevented. If the fallopian tube in the female is blocked, the egg will not be able to reach the uterus. In both cases fertilisation will not take place. Surgical methods can be used to create such blocks.”
Why relevant
Notes that drugs change hormonal balances and can cause side-effects, indicating hormonal therapies have systemic effects and safety considerations.
How to extend
This suggests a student should consider that any RNAi-based modulation of hormones would also need to manage off-target or systemic side effects similar to conventional hormone-altering drugs.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 29: Environment Issues and Health Effects > 29.1.6. DDT > p. 414
Strength: 3/5
“The end result of DDT use is that whole population of predatory birds such as the first hawk (osprey) and of detrirus feeders such as fiddler crab are wiped out. Birds are more vulnerable as DDT interferes with egg shell formation by causing a breakdown in steroid hormones which results in fragile eggs that break before the young can hatch.”
Why relevant
Shows that external chemicals (DDT) can disrupt steroid hormone-related processes, demonstrating that intervening at chemical or molecular levels can alter hormone action and outcomes.
How to extend
A student could infer that molecular interventions (like RNAi) might likewise disrupt or restore hormone pathways, but must account for broader ecological/physiological consequences.
Statement 4
Can RNA interference (RNAi) be used to produce crop plants that are resistant to viral pathogens?
Origin: Web / Current Affairs
Fairness: CA heavy
Web-answerable
"Virtually all of the developments connected to agents of infectious disease can be realized not only for human pathogens, but also for animal and plant pathogens."
Why this source?
- Explicitly states that developments for infectious disease can be applied to plant pathogens, indicating applicability to plants.
- Connects the general technological developments (including RNAi context in the document) to anti-plant pathogen uses.
"RNA interference (RNAi): RNAi technology has the potential to suppress cellular production of certain proteins in the physiological processes to halt undesirable processes or stimulate desirable ones of importance in therapeutic use. Efforts are being made to develop this tool to target disease-causing genes and proteins that are inaccessible to conventional drugs."
Why this source?
- Describes RNAi technology as having the potential to suppress production of specific proteins and to target disease-causing genes, supporting its use as a tool against pathogens.
- Says efforts are being made to develop RNAi to target disease-related genes, implying practical application possibilities such as conferring resistance.
"Although animals generally express fewer variants of the Dicer enzyme than plants, RNAi in some animals produces an antiviral response."
Why this source?
- Notes that RNAi produces an antiviral response in organisms, demonstrating RNAi can act against viruses.
- States that plants have multiple Dicer variants (components of RNAi machinery), implying RNAi pathways exist in plants.
Indian Economy, Vivek Singh (7th ed. 2023-24) > Chapter 11: Agriculture - Part II > 11.8 Genetically Modified (GM) Crops > p. 342
Strength: 5/5
“GM crops are plants whose DNA (a molecule that encodes the Genetic Information) has been modified using Genetic Engineering. The following are some benefits of GM crops: • More nutritional value• Resistance to bacteria, virus and other components that can damage the plant• Longer shelf life• Less costly GM foods and higher yields The Genetic Engineering Appraisal Committee (GEAC) is the apex body for regulating GM crops, in the Ministry of Environment and Forest under the Environment Protections Act 1986. At present, the government allows commercial production of only one GM crop which is BT cotton and is allowed since 2002.”
Why relevant
Defines GM crops as plants whose DNA has been modified and lists 'Resistance to bacteria, virus and other components' as a benefit of genetic engineering.
How to extend
A student could extend this by noting RNAi is one form of genetic modification that can be designed to target viral genes, then seek experimental reports or trials that introduce RNAi constructs into crops and test virus resistance.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 2: PLANT AND ANIMAL KINGDOMS > 2.4 Environment and Ecology > p. 5
Strength: 4/5
“• (ii) Artifcial Selection: Artifcial selection occurs through human activities, when man creates a new environment. For instance, man develops new seeds to increase the yield of crops through artifcial measures such as cross-pollination and hybridisation. Such newly created hybrid seeds are disease and pest resistant and are capable for their adaptation to various types of soils and climatic conditions. Tis process may be benefcial for mankind at present, because it may solve the problem of shortage of food-grains through increased production. But it may prove disastrous in near future, when all natural plants of food crops will disappear from the surface of the Earth.• (iii) Isolation: Isolation also plays an important role in the evolution of morphologically diferentiated populations of species of plants.”
Why relevant
Describes artificial selection and creation of new seeds via human techniques (hybridisation) that produce disease- and pest-resistant varieties.
How to extend
A student can generalise that human-directed genetic changes (including engineered approaches like RNAi) are an accepted route to create disease-resistant plants and then compare methods and efficacy.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 4: BIODIVERSITY > conservation of Biodiversity > p. 27
Strength: 4/5
“Biological necessity: Te growing human population has its own demands on crop yields and animal products. In order to increase continuously the produce from crops and animals, the plant varieties and the animal breeds have to be improved upon continuously. Tis is possible by useful selection of genes by screening a wide range of their wild relatives. Such genetic modifcation can yield improved varieties of plants and useful animals. In order to continue with this biological process of improvement through breeding programmes, it is absolutely necessary to protect and preserve as large a variety of native wildlife as possible.• 3.”
Why relevant
Emphasises that genetic modification (useful selection of genes and screening wild relatives) yields improved, disease-resistant plant varieties.
How to extend
One could treat RNAi as another tool for altering gene function and then evaluate whether targeting viral sequences via RNAi could produce similar 'improved' resistant varieties in trials.
Science , class X (NCERT 2025 ed.) > Chapter 7: How do Organisms Reproduce? > 7.2.5 Vegetative Propagation > p. 117
Strength: 3/5
“There are many plants in which parts like the root, stem and leaves develop into new plants under appropriate conditions. Unlike in most animals, plants can indeed use such a mode for reproduction. This property of vegetative propagation is used in methods such as layering or grafting to grow many plants like sugarcane, roses, or grapes for agricultural purposes. Plants raised by vegetative propagation can bear flowers and fruits earlier than those produced from seeds. Such methods also make possible the propagation of plants such as banana, orange, rose and jasmine that have lost the capacity to produce seeds. Another advantage of vegetative propagation is that all plants produced are genetically similar enough to the parent plant to have all its characteristics.”
Why relevant
Explains vegetative propagation produces genetically similar plants, implying that any engineered trait introduced into a parent (e.g., via genetic modification) can be uniformly propagated.
How to extend
A student might infer that once an RNAi-based resistance trait is introduced into a plant line, vegetative propagation would produce many uniform resistant plants to test field performance.
Indian Economy, Vivek Singh (7th ed. 2023-24) > Chapter 11: Agriculture - Part II > Objectives of Protected Cultivation > p. 354
Strength: 3/5
“• To create a favourable environment for the sustained growth of crop, so as to realise its maximum potential even in adverse climatic conditions.• Protection of plants from abiotic stress (physical or by non-living organism) such as temperature, excess/deficit water, hot and cold waves, and biotic factors such as pest and disease incidences, etc.• Efficient water use with minimum weed infestation.• Enhancing productivity per unit area.• Minimising the use of pesticides in crop production.• Promotion of high value, quality horticultural produce.• Year-round and off-season production of flower, vegetable or fruit crops.• Production of disease-free and genetically better transplants.”
Why relevant
Lists 'Production of disease-free and genetically better transplants' as an objective of protected cultivation, linking disease control with use of improved/genetic approaches.
How to extend
This supports extending the idea that engineered disease-resistance methods (e.g., RNAi constructs) could be deployed in nursery/seedling production and evaluated for reduction of viral incidence.
Pattern takeaway:
UPSC Science & Tech questions often include one option that contradicts the fundamental mechanism of the technology. Focus on 'What does this tool physically do?' rather than 'What is it famous for?'.
How you should have studied
- [THE VERDICT]: Conceptual Sitter. Solvable purely by eliminating the logical contradiction in Statement 3.
- [THE CONCEPTUAL TRIGGER]: Biotechnology > Gene Regulation Tools > RNAi vs CRISPR vs Recombinant DNA.
- [THE HORIZONTAL EXPANSION]: 1. RNAi Mechanism: dsRNA → Dicer → siRNA → RISC → mRNA degradation. 2. Comparison: RNAi (Knock-down/Temporary) vs CRISPR-Cas9 (Knock-out/Permanent). 3. Recombinant DNA Technology: The actual method used for Hormone Replacement (e.g., Insulin). 4. Agrobacterium tumefaciens: The vector often used to deliver these genes in plants. 5. Antisense Technology: The precursor to RNAi (e.g., Flavr Savr tomato).
- [THE STRATEGIC METACOGNITION]: When studying a technology, define its 'Verb'. RNAi = Silences/Cuts. CRISPR = Edits/Cuts DNA. Recombinant DNA = Produces/Adds. Once you know the verb, you can validate the applications without memorizing lists.
Concept hooks from this question
👉 Genetic modification and transgene insertion
💡 The insight
Genetic modification commonly involves inserting foreign genes (transgenes) into an organism's DNA, which is a major class of biotechnological intervention.
High-yield for biotechnology and agriculture topics: distinguishes gene addition approaches from other molecular interventions. Mastery helps answer policy, biosafety and technology-comparison questions (e.g., GM crops vs other genetic methods) and frames debates on regulation and benefit-sharing.
📚 Reading List :
- Indian Economy, Nitin Singhania .(ed 2nd 2021-22) > Chapter 9: Agriculture > GENETICALLY MODIFIED (GM) CROPS > p. 301
🔗 Anchor: "Can RNA interference (RNAi) be used in developing gene-silencing therapies?"
👉 Gene expression controls phenotype
💡 The insight
Phenotypic traits depend on how effectively genes are expressed; altering expression levels changes observable characteristics.
Core concept for genetics and applied biotech questions: links inheritance, molecular mechanisms and practical interventions that modify traits. Understanding expression control enables evaluation of both modification (adding genes) and suppression (silencing) strategies in therapy and crop improvement.
📚 Reading List :
- Science , class X (NCERT 2025 ed.) > Chapter 8: Heredity > 8.2.3 How do these Traits get Expressed? > p. 131
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 13: Our Home: Earth, a Unique Life Sustaining Planet > 13.5 What Keeps Life from Disappearing? > p. 220
- Science , class X (NCERT 2025 ed.) > Chapter 7: How do Organisms Reproduce? > 7.3.1 Why the Sexual Mode of Reproduction? > p. 119
🔗 Anchor: "Can RNA interference (RNAi) be used in developing gene-silencing therapies?"
👉 Molecular causes of cancer: hormones and oncogenic viruses
💡 The insight
Hormones and certain viruses can cause or promote cancer, which is fundamental when considering molecularly targeted therapies.
High-yield for UPSC because it links cancer etiology with biomedical responses and therapeutic design; connects molecular biology with public health and clinical therapy policy; helps answer questions on targeted interventions, prevention strategies, and research priorities.
📚 Reading List :
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 3: Health: The Ultimate Treasure > Be a scientist > p. 37
🔗 Anchor: "Can RNA interference (RNAi) be used to develop therapies for the treatment of ca..."
👉 Plant-derived anticancer drugs and drug discovery
💡 The insight
Natural products such as Taxol and Vincristine are proven cancer therapies, illustrating how biological molecules become therapeutic agents.
Important for questions on drug development, biotechnology and pharmacology; connects agricultural/biological resources to medicine and regulatory/policy issues; enables answers about sources of medicines and innovation pathways.
📚 Reading List :
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 12: Major Crops and Cropping Patterns in India > Table III Pharmaceutical Plants, Drugs and Use > p. 90
🔗 Anchor: "Can RNA interference (RNAi) be used to develop therapies for the treatment of ca..."
👉 Environmental and lifestyle risk factors for cancer
💡 The insight
UV-B exposure, tobacco, diet and pollution significantly change cancer risk and therefore influence treatment priorities and prevention measures.
Crucial for public health and policy-related questions in UPSC; links epidemiology, environmental policy and healthcare planning; useful for framing prevention-focused answers and assessing population-level interventions.
📚 Reading List :
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 19: Ozone Depletion > Effects of human and animal health > p. 271
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 3: Health: The Ultimate Treasure > Be a scientist > p. 37
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > Do you knaw? > p. 66
🔗 Anchor: "Can RNA interference (RNAi) be used to develop therapies for the treatment of ca..."
👉 Endocrine glands and hormone distribution
💡 The insight
Hormone replacement targets hormones produced by specific endocrine glands, so knowing which glands make which hormones and how they act systemically is essential.
High-yield: understanding gland–hormone mapping underpins diagnosis of endocrine disorders and selection of replacement therapies; connects physiology, pathology and clinical treatment; useful for questions on endocrine dysfunction and therapeutic rationale.
📚 Reading List :
- Science , class X (NCERT 2025 ed.) > Chapter 6: Control and Coordination > Activity 6.2 > p. 108
- Science , class X (NCERT 2025 ed.) > Chapter 6: Control and Coordination > Activity 6.3 > p. 109
- Science , class X (NCERT 2025 ed.) > Chapter 7: How do Organisms Reproduce? > 7.3.3 (b) Female Reproductive System > p. 123
🔗 Anchor: "Can RNA interference (RNAi) be used to develop hormone replacement therapies?"
👉 Iodine dependence of thyroxine synthesis and goitre
💡 The insight
Thyroxine synthesis requires iodine, and deficiency causes goitre, directly illustrating a nutritional cause of endocrine failure that may require hormone replacement.
High-yield: links micronutrient deficiency to endocrine disease and public-health interventions (e.g., iodized salt) as well as to clinical replacement (thyroxine); useful for questions bridging nutrition, endocrinology and preventive medicine.
📚 Reading List :
- Science , class X (NCERT 2025 ed.) > Chapter 6: Control and Coordination > Do You Know? > p. 110
🔗 Anchor: "Can RNA interference (RNAi) be used to develop hormone replacement therapies?"
The 'Dicer' enzyme and 'RISC' complex. UPSC has asked about RNAi applications; the next logical step is the machinery. Expect a question asking which cellular components (Dicer/RISC) process double-stranded RNA into silencing signals.
The 'Semantic Contradiction' Hack. Look at the name: RNA *Interference*. To interfere means to obstruct or stop. Look at Statement 3: Hormone *Replacement*. To replace means to add or supply. You cannot 'stop' your way to 'supplying' a missing hormone. Logic dictates Statement 3 is false. Eliminate B and C. Statement 4 (Viral resistance) is a classic application of stopping a virus. Answer is A.
GS3 Agriculture & Biosafety: RNAi is now being used to create 'Bio-clay' sprays for crops. Unlike GM crops, these sprays don't alter the plant's genome permanently, potentially bypassing strict GEAC regulations. This links Science to Regulatory Policy.