Genetic Engineering for UPSC: Recombinant DNA, Bt Cotton, GM Mustard, RNAi, CRISPR-Cas9, DNA Barcoding and Biopiracy
How UPSC Tests Genetic Engineering
🎯 Exam priority: Tier-1. Genetics and biotechnology is the largest slice of Science and Technology: 26 of 104 Prelims questions in ten years (25 per cent). UPSC asked: the transcriptome (2016); GM mustard and the CRISPR pair (2018); whether a biological process to create a seed can be patented (2019); RNA interference and Cas9 (2019); Bollgard Bt cotton (2021); DNA barcoding (2022); and microsatellite DNA (2023). Mains asked about biotechnology and farmers, biopharma, traditional knowledge and patents, and intellectual property on life materials.
Think in four boxes: the toolkit (how DNA is cut, joined and delivered), the products (GM crops, insulin, gene therapy), gene editing and reading tools (CRISPR, barcoding, microsatellites) and the rules and rights (GEAC, patents, biopiracy).
The Toolkit of Recombinant DNA Technology
The toolkit of recombinant DNA technology
Genetic engineering became possible in 1972, when Stanley Cohen and Herbert Boyer cut an antibiotic-resistance gene out of one plasmid with a restriction enzyme and joined it into another with DNA ligase. The five key tools are restriction enzymes, polymerase enzymes, ligases, vectors and a host organism.
Tool | What it does | Detail the exam uses |
Restriction endonuclease | Cuts DNA at a specific recognition sequence ('molecular scissors') | The site is a palindromic sequence; cuts leave single-stranded 'sticky ends'; more than 900 enzymes are known; EcoRI is named from Escherichia coli strain RY13 |
DNA ligase | Joins the cut ends | Works easily on sticky ends cut by the same enzyme |
Vector | Carries the gene into the host and multiplies it | Needs an origin of replication, a selectable marker (such as an antibiotic-resistance gene) and a few cloning sites. Plasmids and bacteriophages are the common vectors |
Ti plasmid of Agrobacterium tumefaciens | Disarmed, it delivers genes into dicot plant cells | Retroviruses, disarmed, are used to deliver genes into animal cells |
Competent host | Bacteria made able to take up DNA | Treated with calcium and given a heat shock; other ways in are micro-injection (animal cells) and the gene gun or biolistics (plant cells) |
Gel electrophoresis | Separates DNA fragments by size | Agarose gel (a polymer from seaweed); DNA moves towards the anode; smaller fragments travel farther; stained with ethidium bromide and seen under UV |
PCR | Amplifies tiny amounts of DNA | Detects HIV early and finds mutations in cancer patients |
GM Crops, Insulin, Gene Therapy and Diagnosis
What the technology has produced
Bt cotton: genes for the Cry proteins of the soil bacterium Bacillus thuringiensis were put into cotton. The toxin exists as an inactive protoxin; in an insect's alkaline gut it becomes active, binds to gut cells and makes pores that kill the insect. cryIAc and cryIIAb control cotton bollworms and cryIAb controls corn borer. Bollgard I and II are Bt cotton technologies (2021 PYQ).
GM mustard (DMH-11): hybrids are made with the barnase and barstar genes of a soil bacterium, which enforce cross-pollination. It is a hybrid-making system, not a pest-resistance trait, and it was developed at Delhi University, not at IARI and Punjab Agricultural University (2018 PYQ).
RNA interference (RNAi): a cell's defence in which a double-stranded RNA silences a matching messenger RNA. It was used to protect tobacco roots from a nematode (Meloidogyne incognita), and is the basis of gene-silencing therapies, cancer research and virus-resistant crops (2019 PYQ), but not of hormone replacement therapy.
Human insulin: chains A and B are made separately in E. coli from synthesised genes and joined by disulphide bonds. The recombinant product avoids the immune reactions that animal insulin can cause.
Gene therapy: the first clinical gene therapy was given in 1990 to a four-year-old girl with adenosine deaminase (ADA) deficiency, using lymphocytes carrying a functional gene delivered by a retroviral vector. It needs repeat infusions unless the gene is put in early embryonic cells.
Transgenic animals: about 95 per cent are mice. The first transgenic cow, Rosie (1997), gave milk with human alpha-lactalbumin.
Diagnosis: PCR finds a pathogen at very low levels by amplifying its nucleic acid; ELISA is based on antigen-antibody binding.
Gene Editing, Reading Tools and 2025-26 Currency
Editing and reading genes
CRISPR-Cas9: a guide RNA leads the Cas9 enzyme, a molecular scissors, to a chosen DNA sequence and cuts it, so a gene can be disabled or corrected (2019 PYQ: Cas9 is not a herbicide or a pest-resistance gene). It is gene editing, not particle physics, and it is different from Belle II (a particle-physics experiment) and blockchain (the technology behind cryptocurrencies) in the 2018 matching question.
DNA barcoding reads a short standard stretch of DNA to identify a species. It separates look-alike species and finds unwanted animal or plant material in processed food, but it cannot give an organism's age (2022 PYQ).
Microsatellite DNA (short repeating sequences that vary between individuals) is used to study genetic diversity and evolutionary relationships among species (2023 PYQ).
Transcriptome is the full range of messenger RNA molecules an organism expresses (2016 PYQ); the genome is the whole DNA.
2025-26 currency (PIB, DBT year-end review)
India's bio-economy grew from $10 billion in 2014 to over $165.7 billion in 2024, with a projection of $300 billion by 2030.
The BioE3 Policy (Biotechnology for Economy, Environment and Employment) has six thematic sectors: bio-based chemicals, enzymes and APIs; smart proteins and functional foods; precision biotherapeutics (cell and gene therapy, mRNA and monoclonal antibodies); climate-resilient agriculture; carbon capture and utilisation; and futuristic marine and space research. India's first National Biofoundry Network of six biofoundries was launched.
Gene-edited crops: a rice line with a mutated DEP1 gene in the popular variety MTU-1010 yields 20 per cent more than the unedited line, and researchers at DBT's BRIC-NIPGR have produced transgene-free mustard lines with CRISPR-Cas9 that accumulate more glucoraphanin.
GenomeIndia: 10,000 whole-genome samples were made accessible to researchers through the Indian Biological Data Centre in January 2025.
Tissue culture: the National Certification System for Tissue Culture Raised Plants has certified over 1.43 billion hardened plants.
Rules, Patents, Biopiracy and How UPSC Could Ask Next
Rules, patents and rights
GEAC (Genetic Engineering Appraisal Committee) decides the validity of GM research and the safety of introducing GM organisms for public use; it works under the Environment (Protection) Act, 1986 and the 1989 Rules.
Patents: an essentially biological process for producing a seed cannot be patented in India and plant varieties are not patentable (they are protected under the PPV&FR Act, 2001) (2019 PYQ). The Intellectual Property Appellate Board was in existence in 2019 but has since been abolished (2021).
Biopiracy is the use of bio-resources by companies without authorisation from, or payment to, the countries and people concerned. The 1997 US patent on a 'new' Basmati variety derived from Indian farmers' varieties, and attempts to patent turmeric and neem uses, are the textbook examples. India protects traditional knowledge through its Biological Diversity Act and the Traditional Knowledge Digital Library.
How UPSC Could Ask This Next
Tool-to-function pairs: restriction enzyme, ligase, vector, PCR, ELISA, CRISPR.
Crop traits: what a given GM crop actually has (Bt, barnase-barstar, herbicide tolerance).
Reading tools: barcoding, microsatellites, transcriptome, metagenomics.
Policy: BioE3, GenomeIndia, GEAC approvals, biopiracy and patents.
Further Reading
NCERT Biology (Class 12) and Geography textbooks, the India State of Forest Report, the MoEFCC Annual Report, the Economic Survey and the official lists cited in this note — the primary sources behind every figure above.
Test Yourself: Practice Questions and PYQs
Twelve practice questions on genetic engineering and biotechnology, followed by the real UPSC Prelims questions and exact Mains questions.
Practice Questions
Q1. Restriction endonucleases cut DNA at specific recognition sequences, which are generally
(a) palindromic sequences
(b) only the ends of chromosomes
(c) regions of repeated RNA
(d) random positions
Show answer
Answer: (a) — Each enzyme recognises a specific palindromic sequence and cuts the strands a little away from its centre, leaving sticky ends.
Q2. In recombinant DNA technology, the enzyme that joins the cut ends of DNA fragments is
(a) ribonuclease
(b) protease
(c) DNA ligase
(d) restriction endonuclease
Show answer
Answer: (c) — Ligase joins fragments, especially sticky ends cut by the same enzyme.
Q3. A disarmed form of which of the following is used to deliver genes into dicot plant cells?
(a) A retrovirus
(b) A bacteriophage
(c) The Ti plasmid of Agrobacterium tumefaciens
(d) A transposon of yeast
Show answer
Answer: (c) — Retroviruses are used for animal cells.
Q4. Consider the following statements about Bt cotton:
1. The Bt toxin exists in the bacterium as an inactive protoxin.
2. It is activated by the alkaline pH of an insect's gut.
3. The toxin attacks the cells of the human gut when cotton seed oil is eaten.
Which of the statements given above are correct?
(a) 1, 2 and 3
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1 and 2 only
Show answer
Answer: (d) — The toxin works on insect midgut cells after activation; statement 3 is not supported.
Q5. RNA interference (RNAi) works by
(a) cutting DNA with Cas9
(b) copying DNA with a polymerase
(c) joining DNA ends with ligase
(d) silencing a specific messenger RNA with a complementary double-stranded RNA
Show answer
Answer: (d) — It is a cellular defence and was used to protect tobacco roots from a nematode.
Q6. The first clinical gene therapy in 1990 was given for
(a) cystic fibrosis
(b) sickle cell anaemia
(c) adenosine deaminase (ADA) deficiency
(d) haemophilia
Show answer
Answer: (c) — A four-year-old girl received lymphocytes with a functional ADA gene.
Q7. Which technique amplifies very small amounts of DNA, making it possible to detect a virus such as HIV before symptoms appear?
(a) Gel electrophoresis
(b) Biolistics
(c) Polymerase chain reaction (PCR)
(d) ELISA
Show answer
Answer: (c) — ELISA detects antigens or antibodies; PCR amplifies nucleic acid.
Q8. About what share of all existing transgenic animals are mice?
(a) 95 per cent
(b) 25 per cent
(c) 10 per cent
(d) 50 per cent
Show answer
Answer: (a) — Mice are used because their physiology and genetics are well understood.
Q9. In India, decisions on the validity of GM research and the safety of introducing GM organisms for public use are taken by the
(a) National Biodiversity Authority
(b) Bureau of Indian Standards
(c) Genetic Engineering Appraisal Committee
(d) Central Pollution Control Board
Show answer
Answer: (c) — GEAC works under the Environment (Protection) Act, 1986 and its 1989 Rules.
Q10. Consider the following statements about GM mustard (DMH-11):
1. It uses the barnase and barstar genes to enforce cross-pollination.
2. It was developed jointly by IARI and Punjab Agricultural University.
Which of the statements given above is/are correct?
(a) Neither 1 nor 2
(b) Both 1 and 2
(c) 2 only
(d) 1 only
Show answer
Answer: (d) — It came from Delhi University.
Q11. 'Biopiracy' refers to
(a) use of bio-resources or traditional knowledge by companies without authorisation or compensation
(b) hijacking of ships carrying biological samples
(c) illegal capture of wild animals for zoos
(d) copying of crop varieties by farmers
Show answer
Answer: (a) — The 1997 US patent on a Basmati variety is a classic example.
Q12. Which of the following is NOT one of the six thematic sectors of the BioE3 Policy?
(a) Precision biotherapeutics
(b) Nuclear fuel fabrication
(c) Carbon capture and utilisation
(d) Climate-resilient agriculture
Show answer
Answer: (b) — The six sectors are bio-based chemicals, smart proteins, precision biotherapeutics, climate-resilient agriculture, carbon capture and utilisation, and marine and space research.
UPSC Previous Year Questions (PYQs)
Real UPSC Prelims questions, checked against the official paper and answer key.
Q1. (2016) In the context of the developments in Bioinformatics, the term 'transcriptome', sometimes seen in the news, refers to
(a) a range of enzymes used in genome editing
(b) the full range of mRNA molecules expressed by an organism
(c) the description of the mechanism of gene expression
(d) a mechanism of genetic mutations taking place in cells
Show answer
Answer: (b) — The transcriptome is the full set of RNA transcripts, mainly messenger RNA, that a cell or organism produces at a given time. It is different from the genome (all the DNA) and from genome-editing enzymes.
Q2. (2018) With reference to the Genetically Modified mustard (GM mustard) developed in India, consider the following statements:
1. GM mustard has the genes of a soil bacterium that give the plant the property of pest-resistance to a wide variety of pests.
2. GM mustard has the genes that allow the plant cross-pollination and hybridization.
3. GM mustard has been developed jointly by the IARI and Punjab Agricultural University.
Which of the statements given above is/are correct?
(a) 1, 2 and 3
(b) 2 only
(c) 2 and 3 only
(d) 1 and 3 only
Show answer
Answer: (b) — GM mustard (DMH-11) uses the barnase and barstar genes from a soil bacterium to enforce cross-pollination and make hybrids; it is not about pest resistance, and it was developed at Delhi University, not IARI and Punjab Agricultural University. Only statement 2 is right.
Q3. (2018) Consider the following pairs: Terms sometimes see in news Context/Topic
1. Belle II experiment Artificial Intelligence
2. Blockchain technology Digital/Cryptocurrency
3. CRISPR - Cas9 Particle Physics
Which of the pairs given above is/are correctly matched?
(a) 2 only
(b) 1 and 3 only
(c) 2 and 3 only
(d) 1, 2 and 3
Show answer
Answer: (a) — Belle II is a particle-physics experiment in Japan (not AI), CRISPR-Cas9 is a gene-editing tool (not particle physics) and blockchain is the technology behind cryptocurrencies. Only pair 2 is matched correctly.
Q4. (2019) Consider the following statements:
1. According to the Indian Patents Act, a biological process to create a seed can be patented in India.
2. In India, there is no Intellectual Property Appellate Board.
3. Plant varieties are not eligible in the patented in India.
Which of the statements given above is/are correct?
(a) 2 and 3 only
(b) 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Show answer
Answer: (b) — The Patents Act excludes essentially biological processes for producing plants or animals, and plant varieties are not patentable (they are protected under the PPV&FR Act, 2001). The Intellectual Property Appellate Board did exist in 2019 (it was abolished in 2021), so statement 2 was wrong then. Only statement 3 was right.
Q5. (2019) RNA interference (RNAi)' technology has gained popularity in the last few years. Why?
1. It is used in developing gene silencing therapies.
2. It can be used in developing therapies for the treatment of cancer.
3. It can be used to develop hormone replacement therapies.
4. It can be used to produce crop plants that are resistant to viral pathogens.
Select the correct answer using the code given below.
(a) 1, 2 and 4 only
(b) 2 and 3 only
(c) 1 and 4 only
(d) 1 and 3 only
Show answer
Answer: (a) — RNA interference silences specific genes. It underpins gene-silencing therapies, is being explored against cancer and can make crop plants resist viral pathogens. It is not used to develop hormone replacement therapy, so 1, 2 and 4.
Q6. (2019) What is Cas9 protein that is often mentioned in news?
(a) A molecular scissors used in targeted gene editing
(b) A herbicidal substance synthesized in genetically modified crops
(c) A gene that makes plants pest-resistant
(d) A biosensor used in the accurate detection of pathogens in patients
Show answer
Answer: (a) — Cas9 is an enzyme that acts as molecular scissors: guided by an RNA, it cuts DNA at a chosen spot, which is the basis of CRISPR-Cas9 gene editing.
Q7. (2020) Which of the following statements are correct regarding the general difference between plant and animal cells?
1. Plant cells have cellulose cell walls whilst animal cells do not.
2. Plant cells do not have plasma membrane unlike animal cells which do.
3. Mature plant cell has one large vacuole whilst animal cell has many small vacuoles.
Select the correct answer using the code given below.
(a) 1, 2 and 3
(b) 1 and 3 only
(c) 1 and 2 only
(d) 2 and 3 only
Show answer
Answer: (b) — Plant cells have a cellulose cell wall that animal cells lack, and a mature plant cell has one large central vacuole while animal cells have several small ones. Both plant and animal cells have a plasma membrane, so statement 2 is wrong.
Q8. (2020) With reference to the current trends in the cultivation of sugarcane in India, consider the following statements:
1. A substantial saving in seed material is made when 'bud chip settlings' are raised in a nursery and transplanted in the main field.
2. When direct planting of seeds is done, the germination percentage is better with single-budded setts as compared to setts with many buds.
3. If bad weather conditions prevail when seeds are directly planted, single-budded seeds have better survival as compared to large setts.
4. Sugarcane can be cultivated using settlings prepared from tissue culture.
Which of the statements given above is/are correct?
(a) 1 and 4 only
(b) 2, 3 and 4 only
(c) 3 only
(d) 1 and 2 only
Show answer
Answer: (a) — Seedlings raised from bud chips in a nursery save seed cane (statement 1), and tissue-culture seedlings are used to propagate sugarcane (statement 4). UPSC's key rejects statements 2 and 3 about single-budded setts.
Q9. (2021) Bollgard I and Bollgard II technologies are mentioned in the context of
(a) developing genetically modified crop plants
(b) clonal propagation of crop plants
(c) production of biofertilizers
(d) production of plant growth substances
Show answer
Answer: (a) — Bollgard I and II are Bt cotton technologies: genes from the bacterium Bacillus thuringiensis are put into cotton so that it resists bollworms. They are genetically modified crops.
Q10. (2022) Consider the following statements: DNA Barcoding can be a tool to:
1. assess the age of a plant or animal.
2. distinguish among species that look alike.
3. identify undesirable animal or plant materials in processed foods.
Which of the statements given above is/are correct?
(a) 3 only
(b) 2 and 3 only
(c) 1 only
(d) 1 and 2 only
Show answer
Answer: (b) — DNA barcoding reads a short standard stretch of DNA to identify a species, so it can tell look-alike species apart and spot unwanted animal or plant material in processed food. It cannot give the age of an organism.
Q11. (2023) 'Microsatellite DNA' is used in the case of which one of the following?
(a) Studying the evolutionary relationships among various species of fauna
(b) Stimulating 'stem cells' to transform into diverse functional tissues
(c) Assessing the efficacy of drugs by conducting series of drug trials in a population
(d) Promoting clonal propagation of horticultural plants
Show answer
Answer: (a) — Microsatellites are short repeated DNA sequences that vary between individuals and species, which makes them useful for studying genetic diversity and evolutionary relationships. Stem-cell stimulation, clonal propagation and drug trials use other methods.
Mains Practice Questions
Use these to frame full-length answers. You don't have to answer one exactly — they show the angles UPSC tests, so let them guide which points you cover.
How can biotechnology help to improve the living standards of farmers? Give examples of Bt cotton, gene-edited crops and tissue culture.
What is the present world scenario of intellectual property rights with respect to life materials? Why have so few Indian patents been commercialised?
How is the Government of India protecting traditional knowledge of medicine from patenting by pharmaceutical companies?
Explain why there is so much activity in the field of biotechnology in India and how it has benefitted biopharma.
Compare GM crops and gene-edited crops in terms of technology, regulation and public acceptance.
UPSC Mains — Previous Years’ Questions on this topic (last 10 years)
These are the actual GS Mains questions UPSC has asked on this theme — real proof of how, and when, it is tested. Try to write a full answer to each.
2026 (GS-III): Explain by giving two examples, how biotechnology has helped the Indian farmers in processing their perishable crops.
2025 (GS-III): How can India achieve energy independence through clean technology by 2047 ? How can biotechnology can play a crucial role in this endeavour?
2024 (GS-III): What is the present world scenario of intellectual property rights with respect to life materials? Although, India is second in the world to file patents, still only a few have been commercialized. Explain the reasons behind this less commercialization.
2021 (GS-III): What are the research and developmental achievements in applied biotechnology? How will these achievements help to uplift the poorer sections of the society?
2019 (GS-III): How is the Government of India protecting traditional knowledge of medicine from patenting by pharmaceutical companies?
2019 (GS-III): How can biotechnology help to improve the living standards of farmers?
2018 (GS-III): Why is there so much activity in the field of biotechnology in our country? How has this activity benefitted the field of biopharma?