Biotechnology in UPSC Prelims: 19 questions on what the technique does, not its name

Most aspirants prepare biotechnology as a glossary: CRISPR, RNAi, SCNT, DNA barcoding, each with a one-line definition copied from the news. The past papers suggest a glossary isn’t enough. UPSC rarely asks you to expand an abbreviation. It asks what the technique is used for, and it often builds the wrong options from what the name sounds like.

This post looks at the 19 biotechnology and genetics questions asked from 2016 to 2026 and turns them into a plan.

What the numbers say

Three things stand out.

It almost never skips a year. Ten of the 11 papers had at least one biotechnology question. Only 2024 had none.

It peaked in 2021. That paper had 4 questions, back to back as questions 65, 66, 67 and 69. 2019 had 3. Every other year had 1 or 2, including 2 in 2026.

The format is split almost evenly. 8 of the 19 were single-answer questions: “what is Cas9”, “what does transcriptome refer to”, “what is SCNT used for”. The other 11 gave you statements to judge. Those statement sets have grown more common: every question since 2025 has been one.

What UPSC is really testing

By our count, the 19 questions fall into four groups:

• What it is used for: 7 questions. Genome sequencing in agriculture, Somatic Cell Nuclear Transfer, RNA interference, pronuclear transfer, Bollgard, DNA barcoding and microsatellite DNA.
• What the term means: 6. Transcriptome, Cas9, aerial metagenomics, recombinant vector vaccines, monoclonal antibodies and genetic medicine.
• What a lab can actually do: 4. Whether DNA can be made to replicate outside a cell, whether human embryos and germline cells can be edited, whether viruses grow on an artificial medium, and when mitochondrial replacement can be done.
• Indian programmes: 2. GM mustard in 2018 and the GenomeIndia Project in 2026.

So 13 of the 19 questions asked what a technique is or does. Only the 2 Indian programme questions asked who developed or funded something, and no question asked who invented a technique or when.

The other thing to notice is the range. These questions cover crops (genome sequencing, GM mustard, Bollgard), human reproduction (pronuclear transfer, mitochondrial replacement, embryo editing), medicine (monoclonal antibodies, genetic medicine, vaccines) and biodiversity (DNA barcoding, aerial metagenomics, microsatellites). A technique from any of these can turn up.

The trap most questions share

The wrong option is what the name sounds like. “Aerial” metagenomics sounds like birds or drones. It means reading all the DNA in a sample of air. “Microsatellite” DNA sounds like space technology. It is just short, repeated DNA used as a genetic marker. “Transcriptome” sounds like the process of gene expression. It is the full set of mRNA an organism expresses. GenomeIndia sounds like part of the Human Genome Project. It is a separate Indian project.

This is the pattern in the single-answer questions. Here is how the trap was set in each one where it came from the name or a familiar neighbour:

Technique	What it actually does	What the trap borrowed
Transcriptome (2016)	Full range of mRNA expressed	The word “transcription”
SCNT (2017)	Reproductive cloning of animals	A medical-sounding use
Cas9 (2019)	Molecular scissors for gene editing	GM crops, because of CRISPR
Pronuclear transfer (2020)	Prevents mitochondrial disease	IVF words like “fertilisation”
Aerial metagenomics (2023)	DNA collected from air in one go	Birds, drones
Microsatellite DNA (2023)	Studying relationships among species	The word “satellite”

The statement sets have a second trap, and it runs the other way. In 5 of the 11, every statement was true: genome sequencing (2017), germline and embryo editing (2020), recombinant vector vaccines (2021), mitochondrial replacement (2021) and monoclonal antibodies (2025). The 2020 question is the clearest case. Editing human embryos sounds banned, so it sounds impossible. The question asked what can be done, and all three statements were correct.

When a statement was false, it usually stretched the technique beyond its job:

• DNA barcoding identifies species. It cannot tell an organism’s age (2022).
• Genetic medicine targets specific genes. It does not change the entire DNA sequence (2026).
• RNAi silences genes. It is not used for hormone replacement therapy (2019).
• Bacteria and fungi grow on artificial media. Viruses need living cells (2021).

The two Indian programme questions borrowed from a famous neighbour instead. GM mustard’s genes come from a soil bacterium, like Bt cotton’s, so students assumed they give pest resistance. They are for making hybrids. And GenomeIndia was not part of the Human Genome Project.

How to prepare

1. For each technique, write what it does, not what it stands for. One line on its job, one line on where it is used (crops, medicine, reproduction or biodiversity). “Cas9: cuts DNA at a chosen spot, for gene editing” is worth more than the expansion of CRISPR.

2. Write one line on what it is not. Aerial metagenomics: not about birds. Microsatellite: not technology. DNA barcoding: not a dating method. GM mustard: not for pest resistance. This is where most of the trap options in these 19 questions came from.

3. Know the limit of each technique. The false statements claimed too much: barcoding that tells age, genetic medicine that rewrites the whole genome, viruses grown on a plain medium. If a statement makes a technique sound like it does everything, check it.

4. Don’t reject what sounds unethical or futuristic. Germline editing, human-pig chimeras and mitochondrial replacement were all real, and all appeared in true statements. “It’s controversial” is not the same as “it’s impossible”.

5. Learn the basics of the Indian programmes. For GM mustard and GenomeIndia, UPSC asked who developed or funded it and what it is for. Delhi University developed GM mustard. The Department of Biotechnology funds GenomeIndia.

6. Solve the past questions before reading more. Start with the biotechnology and genetics questions, then see the wider biotechnology and health topic.

What to skip: inventors, dates of discovery and the full form of every abbreviation. None of the 19 questions turned on them.

Two questions that show the pattern

2023 · What the term means. ‘Aerial metagenomics’ best refers to which one of the following situations? Collecting DNA samples from the air in a habitat at one go. The traps were the genetic makeup of birds and drones sent to collect samples, both drawn from the word “aerial”. See the question

2022 · The limit of a technique. Three statements on what DNA barcoding can be used for. It can tell apart species that look alike, and it can detect undeclared plant or animal material in processed food. It cannot assess an organism’s age. The trap was confusing it with a dating method. See the question

For the other high-yield areas, see the must-do list. Species questions also reward knowing what something does over what it’s called, and we wrote about them here.