Introduction: Genetic engineering in medicine applies molecular biology tools to design therapies, diagnostics, and biologics that transform patient care. For B.Pharm students, key areas include gene therapy, recombinant protein drugs, monoclonal antibodies, vaccine platforms (mRNA, viral vectors), CRISPR-based genome editing, pharmacogenomics-guided therapy, and advanced delivery systems like lipid nanoparticles and viral vectors. Understanding vector design, expression systems, safety, regulatory requirements, immunogenicity, and off-target effects is essential for drug development and clinical translation. This topic links basic molecular techniques to pharmaceutical formulation, quality control, and therapeutic application, preparing students for roles in research, regulatory affairs, and clinical pharmacology. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. Which enzyme is primarily used to create double-stranded breaks at specific DNA sequences in CRISPR-Cas9 genome editing?
- Reverse transcriptase
- Taq polymerase
- Cas9 endonuclease
- DNA ligase
Correct Answer: Cas9 endonuclease
Q2. Which viral vector is most commonly used for long-term gene expression in non-dividing cells with low immunogenicity?
- Adenovirus
- Adeno-associated virus (AAV)
- Lentivirus
Correct Answer: Adeno-associated virus (AAV)
Q3. What is the main advantage of codon optimization when expressing therapeutic proteins in heterologous hosts?
- Reduces need for purification
- Improves mRNA stability and translation efficiency
- Eliminates post-translational modifications
- Prevents plasmid replication
Correct Answer: Improves mRNA stability and translation efficiency
Q4. Which expression system is preferred for producing proteins requiring complex human-like glycosylation?
- Escherichia coli
- Yeast (Saccharomyces)
- Insect cells (baculovirus)
- Mammalian cells (CHO)
Correct Answer: Mammalian cells (CHO)
Q5. In gene therapy, what does ex vivo delivery refer to?
- Direct injection of vector into patient tissues
- Modifying cells outside the body and reinfusing them
- Using mRNA vaccines for in situ protein expression
- Topical application of plasmid DNA
Correct Answer: Modifying cells outside the body and reinfusing them
Q6. Which of the following is a key safety concern unique to integrating viral vectors?
- Short-lived expression
- Insertional mutagenesis
- Poor transduction efficiency
- High production cost
Correct Answer: Insertional mutagenesis
Q7. Which molecular tool is commonly used for transient gene silencing via sequence-specific mRNA degradation?
- siRNA
- CRISPR-Cas9 nuclease
- Recombinant antibody
- Reverse transcriptase inhibitor
Correct Answer: siRNA
Q8. What is the role of a promoter in an expression construct for recombinant protein production?
- Terminate transcription
- Bind ribosomes for translation
- Initiate and regulate transcription
- Facilitate plasmid replication
Correct Answer: Initiate and regulate transcription
Q9. Which regulatory standard specifically governs manufacture of biologics, including genetically engineered products?
- ICH Q10
- Good Manufacturing Practice (GMP)
- ICH Q12
- Good Clinical Practice (GCP)
Correct Answer: Good Manufacturing Practice (GMP)
Q10. Monoclonal antibodies produced by recombinant DNA technology most commonly use which host for large-scale commercial production?
- Human primary cells
- CHO cells
- E. coli
- Baculovirus-infected insect cells
Correct Answer: CHO cells
Q11. Which component of mRNA vaccine formulations primarily facilitates cellular uptake and endosomal escape?
- Polysorbate 80
- Lipid nanoparticles
- Aluminum salts
- Polyethylene glycol alone
Correct Answer: Lipid nanoparticles
Q12. Pharmacogenomics in genetic engineering helps to:
- Standardize dosing for all patients
- Predict patient-specific drug response and adverse effects
- Replace clinical trials entirely
- Ensure viral vector integration
Correct Answer: Predict patient-specific drug response and adverse effects
Q13. Which assay is most suitable for quantifying low-abundance transgene copy number in clinical samples?
- Western blot
- qPCR or digital PCR
- SDS-PAGE
- ELISA for protein
Correct Answer: qPCR or digital PCR
Q14. What is a biosimilar?
- A chemically identical small-molecule generic
- A biologic highly similar to an approved reference biologic with no clinically meaningful differences
- A vaccine produced by recombinant DNA
- An experimental gene therapy
Correct Answer: A biologic highly similar to an approved reference biologic with no clinically meaningful differences
Q15. Which selectable marker is commonly used in bacterial plasmids for cloning recombinant DNA?
- GFP fluorescence
- Ampicillin resistance gene (bla)
- Luciferase gene
- Neomycin phosphotransferase for mammalian cells
Correct Answer: Ampicillin resistance gene (bla)
Q16. In CAR-T cell therapy, what is the primary function of the chimeric antigen receptor?
- Enhance T cell migration to bone marrow only
- Enable T cells to recognize and kill specific tumor antigens
- Suppress immune responses against tumors
- Deliver genes to tumor cells
Correct Answer: Enable T cells to recognize and kill specific tumor antigens
Q17. Which component is critical for minimizing off-target effects in CRISPR-Cas9 editing?
- High plasmid copy number
- Optimized guide RNA specificity and reduced exposure time
- Using larger viral vectors
- Increasing Cas9 concentration indefinitely
Correct Answer: Optimized guide RNA specificity and reduced exposure time
Q18. Which method is commonly used to purify recombinant proteins based on affinity tags?
- Size-exclusion chromatography only
- Ion-exchange chromatography only
- Affinity chromatography (e.g., His-tag with Ni-NTA)
- Ultracentrifugation
Correct Answer: Affinity chromatography (e.g., His-tag with Ni-NTA)
Q19. Which of the following describes germline gene editing?
- Editing somatic cells for therapeutic effect in a patient
- Modifying gametes or embryos leading to heritable changes
- Using small molecules to modulate gene expression
- Administering therapeutic proteins
Correct Answer: Modifying gametes or embryos leading to heritable changes
Q20. What is the primary role of a polyadenylation signal in an mRNA expression cassette?
- Initiate translation
- Enhance mRNA stability and termination of transcription
- Bind ribosomes
- Act as a selectable marker
Correct Answer: Enhance mRNA stability and termination of transcription
Q21. Which diagnostic technique uses next-generation sequencing to identify genetic variants relevant to personalized medicine?
- Sanger sequencing only
- Whole-exome or targeted NGS panels
- Immunohistochemistry
- Western blot
Correct Answer: Whole-exome or targeted NGS panels
Q22. What is immunogenicity in the context of therapeutic proteins and gene therapies?
- Ability of a drug to cross the blood-brain barrier
- Potential to trigger an unwanted immune response
- Rate of protein degradation
- Efficiency of transduction
Correct Answer: Potential to trigger an unwanted immune response
Q23. Which feature distinguishes a replication-deficient viral vector used in gene therapy?
- It replicates rapidly in host cells
- It cannot replicate due to deletion of essential genes
- It integrates randomly into mitochondrial DNA
- It always causes systemic infection
Correct Answer: It cannot replicate due to deletion of essential genes
Q24. Which regulatory document provides guidance on quality, safety, and efficacy of cell and gene therapy products?
- ICH Q9 only
- FDA/EMA guidance documents for gene and cell therapies
- Pharmacopoeial monographs exclusively
- ICH Q8 alone
Correct Answer: FDA/EMA guidance documents for gene and cell therapies
Q25. Which reporter gene is commonly used to monitor transfection efficiency in research?
- GFP (green fluorescent protein)
- Beta-lactamase only
- Insulin gene
- Albumin
Correct Answer: GFP (green fluorescent protein)
Q26. Antisense oligonucleotides exert their therapeutic effect primarily by:
- Editing genomic DNA sequences permanently
- Binding target mRNA to alter splicing or promote degradation
- Increasing translation through ribosomal activation
- Stimulating antibody production
Correct Answer: Binding target mRNA to alter splicing or promote degradation
Q27. Which of the following is a common method to reduce immune recognition of viral vectors?
- Use high immunogenic promoters
- Engineer capsid variants and immune-evasive modifications
- Administer vectors without screening
- Increase vector dose indiscriminately
Correct Answer: Engineer capsid variants and immune-evasive modifications
Q28. What does an epitope mapping study help determine in therapeutic antibody development?
- Antibody half-life only
- Exact antigen region recognized by the antibody
- Vector integration site
- Promoter strength
Correct Answer: Exact antigen region recognized by the antibody
Q29. Which of the following best describes off-target effects in genome editing?
- Desired edits at the target locus only
- Unintended modifications at non-target genomic sites
- Enhanced on-target specificity
- Improved delivery efficiency
Correct Answer: Unintended modifications at non-target genomic sites
Q30. For B.Pharm students, why is understanding vector biodistribution important in gene therapy development?
- It determines the color of the formulation
- It informs target tissue delivery, safety, and potential off-target toxicity
- Only relevant for non-therapeutic research
- Replaces the need for clinical trials
Correct Answer: It informs target tissue delivery, safety, and potential off-target toxicity
I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.
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