STUDY MATERIAL · GATE BT
GATE Recombinant DNA Technology previous year questions and notes
Every Recombinant DNA Technology and Tools question from 7 GATE papers (2019–2026), solved step by step and checked against the organising institute’s official answer key — with notes for each topic, a formula sheet and practice questions.
- previous-year questions
- 54previous-year questions
- worked solutions, checked against the key
- 53worked solutions, checked against the key
- GATE papers, 2019–2026
- 7GATE papers, 2019–2026
- topics with notes
- 7topics with notes
TOPICS
Seven topics, in the order they are taught
Cut from the official GATE 2027 syllabus. Each topic has notes, the formulas you need, every previous-year question on it with a checked solution, and practice questions.
- TOPIC 01
Restriction enzymes, cloning vectors and expression vectors
Recombinant DNA work uses three sets of tools.
10 previous-year questions · 16 marks · 6 practice
- TOPIC 02
DNA libraries, gene cloning and recombinant protein production
A DNA library is a collection of cloned fragments representing either a whole genome (a genomic library) or the mRNA population of a cell at one time (a cDNA library).
5 previous-year questions · 7 marks · 5 practice
- TOPIC 03
PCR, sequencing, blotting and DNA fingerprinting
Tools for copying, labelling, reading and comparing specific nucleic-acid sequences: PCR and its variants (with the copy-number, Tm and qPCR relations), probe labelling, Sanger and next-generation sequencing, Southern and Northern blotting, in-situ hybridisation, and DNA fingerprinting by RFLP, RAPD and repeat-length markers.
8 previous-year questions · 13 marks · 7 practice
- TOPIC 04
Mutagenesis, CRISPR-Cas, biosensors and interaction tools
Notes cover site-directed mutagenesis (Kunkel, overlap-extension PCR, whole-plasmid PCR with DpnI, cassette), the CRISPR-Cas system (natural immunity, sgRNA, PAM, HNH/RuvC, NHEJ vs HDR, nickase, dCas9, base and prime editors, Cas12a, Cas13, off-target effects), biosensor components, transducers and performance (with the enzyme linear range, potentiometric slope and LOD convention), DNA-protein interaction tools (EMSA with fraction-bound and Kd, DNase I footprinting, ChIP, one-hybrid), protein-protein interaction tools (Y2H, Co-IP, pull-down, FRET, BiFC, SPR, AP-MS), and genomics/proteomics-scale approaches including ESI mass spectrometry, for GATE BT Recombinant DNA Technology.
3 previous-year questions · 5 marks · 6 practice
- TOPIC 05
Microscopy and spectroscopy
Microscopy and spectroscopy answer two different questions about biological material.
8 previous-year questions · 15 marks · 7 practice
- TOPIC 06
Electrophoresis, microarrays, immunoassays and flow cytometry
Notes for GATE BT on Electrophoresis, Microarrays, Immunoassays and Flow Cytometry.
9 previous-year questions · 13 marks · 6 practice
- TOPIC 07
Bioinformatics: databases, sequence alignment, phylogeny and structure prediction
Bioinformatics turns raw sequence and structure data into biological insight.
11 previous-year questions · 16 marks · 7 practice
WHERE THE QUESTIONS FALL
54 questions, by topic and year
Counts across the BT papers of each year. A count of what was asked, not a forecast of what will be. The topic tags are IAE’s reading of each question, and every question links back to its paper.
| Topic | 2019 | 2020 | 2022 | 2023 | 2024 | 2025 | 2026 | Total |
|---|---|---|---|---|---|---|---|---|
| Enzymes & vectors | · | 4 | 3 | 2 | 1 | · | · | 10 |
| Libraries & cloning | · | 4 | · | · | · | 1 | · | 5 |
| PCR & sequencing | 1 | 1 | 1 | 2 | 3 | · | · | 8 |
| Editing & interactions | 1 | · | · | 1 | · | · | 1 | 3 |
| Microscopy & spectroscopy | 2 | · | 1 | 1 | 1 | 3 | · | 8 |
| Assays & electrophoresis | 3 | 1 | · | 1 | · | 2 | 2 | 9 |
| Bioinformatics | 3 | 1 | 2 | 3 | · | 1 | 1 | 11 |
The 2018 paper is not included: the only copy we could find carries a coaching institute's watermark, so its crops cannot be published. The hosted 2021 file is an image scan with no text layer and no key. BT 2019 is taken from IIT Madras's own copy of the paper and key (via the Internet Archive).
How we check solutions: editorial standards.
Recombinant DNA Technology formulas by topic
Preparing in Kolkata? See IAE Academy’s GATE BT coaching.
THE OFFICIAL SYLLABUS
What each paper lists under Recombinant DNA Technology and Tools
Verbatim from the GATE 2027 syllabus PDF: BT Section 6, “Recombinant DNA technology and Other Tools in Biotechnology”, in its four printed parts — recombinant DNA technology, molecular tools, analytical tools and computational tools.
GATE BT
Recombinant DNA technology: Restriction and modification enzymes; Vectors - plasmids, bacteriophage and other viral vectors, cosmids, Ti plasmid, bacterial and yeast artificial chromosomes; Expression vectors; cDNA and genomic DNA library Gene isolation and cloning, strategies for production of recombinant proteins; Transposons and gene targeting, Recombination-based gene cloning. Molecular tools: Polymerase chain reaction; DNA/RNA labelling and Sangers and next generation sequencing; Southern and northern blotting; In-situ hybridization; DNA fingerprinting, RAPD, RFLP; Site-directed mutagenesis; CRISPR-Cas; Biosensing and biosensors; DNA-protein and protein-protein interaction tools; Genomics and proteomics-based approaches. Analytical tools: Principles of microscopy - light, electron, fluorescence and confocal; Principles of spectroscopy- UV, visible, fluorescence, CD, IR, FT-IR, MS, NMR; Electrophoresis; Micro- arrays; Enzymatic assays; Immunoassays - ELISA, RIA, immunohistochemistry; Immunoblotting; Flow cytometry; Whole genome and ChIP sequencing. Computational tools: Bioinformatics resources and search tools; Sequence and structure databases; Sequence analysis - sequence file formats, scoring matrices, alignment, phylogeny; Genomics, proteomics, metabolomics; Gene prediction; Functional annotation; Secondary structure and 3D structure prediction; Knowledge discovery in biochemical databases; Metagenomics; Metabolic engineering and systems biology.
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