1. Which technology is most commonly used for gene editing?
a) ZFNs
b) TALENs
c) CRISPR-Cas9
d) Meganucleases
2. CRISPR-Cas9 functions by:
a) Cutting DNA at a specific location
b) Inserting a new DNA sequence
c) Both cutting DNA and inserting a new sequence
d) Preventing genes from being expressed
3. Cas9 is:
a) A protein that cuts DNA
b) The guide RNA molecule
c) Part of the bacterial immune system
d) All of the above
4. Guide RNA is important because it:
a) Cuts DNA at the target location
b) Binds to Cas9 protein
c) Specifies the DNA target sequence
d) Helps integrate new DNA
5. What type of genetic alteration is made during gene editing?
a) Point mutation
b) Deletion
c) Insertion
d) All of the above
6. Which phase of the cell cycle is ideal for gene editing?
a) G1 phase
b) S phase
c) G2 phase
d) M phase
7. Gene drives are a proposed application of gene editing to:
a) Control insect-borne diseases
b) Treat genetic disorders
c) Modify crops
d) All of the above
8. Somatic cell gene editing:
a) Alters the germline
b) Affects an individual only
c) Can be passed to offspring
d) Cures genetic disease
9. What are homology arms?
a) Sequences that flank the target site
b) Guide RNA molecules
c) Templates for DNA repair
d) Cas9 binding proteins
10. CRISPR has advantages over ZFNs and TALENs because it is:
a) More specific
b) Easier to design
c) Cheaper to produce
d) All of the above
11. Off-target effects occur when:
a) The gene of interest is not edited
b) Unintended DNA sites are altered
c) The donor DNA is not integrated
d) The cell fails to repair itself
12. Mosaicism arises from:
a) Off-target effects
b) DNA damage caused by editing
c) Incomplete editing in early embryos
d) All of the above
13. Which type of cell lineage is hereditary?
a) Somatic
b) Germline
c) Embryonic
d) None of the above
14. Efficiency of homology-directed repair can be improved by:
a) Using longer homology arms
b) Increasing the Cas9 concentration
c) Causing site-specific DNA breaks
d) All of the above
15. Germline editing could allow:
a) Treatment of mitochondrial diseases
b) Prevention of genetic disorders
c) Generation of transgenic animals
d) All of the above
16. What term refers to editing embryos, eggs or sperm?
a) Somatic cell editing
b) Germline editing
c) Genome editing
d) Ex vivo gene therapy
17. Inserting a selectable marker allows identification of cells that have been:
a) Transfected
b) Selected
c) Successfully edited
d) Destroyed by CRISPR
18. The first human clinical trial approved for somatic cell gene editing targeted:
a) Cystic fibrosis
b) Cancer
c) HIV/AIDS
d) Blindness
19. Gene drives could help control mosquito-borne diseases by:
a) Altering mosquito genes rendering them unable to transmit pathogens
b) Releasing mosquitoes resistant to the diseases
c) Both a and b
d) None of the above
20. CRISPR has been investigated to treat which type of genetic disorder?
a) Sickle cell anemia
b) Duchenne muscular dystrophy
c) Cystic fibrosis
d) All of the above
21. False positive selection can occur if:
a) The donor DNA fails to insert
b) The Cas9 protein is not expressed
c) The target site is not cleaved by Cas9
d) The selectable marker is incorporated without editing
22. Zinc finger nucleases work by fusing:
a) A nuclease to a programmable DNA-binding domain
b) A guide RNA and Cas9 protein
c) A TAL effector domain and FokI nuclease
d) Homology arms for HDR
23. To generate knockout cells, gene editing typically involves:
a) Inserting a complete gene
b) Deleting part of the gene sequence
c) Correcting a mutation
d) Adding selectable markers
24. What property of CRISPR makes it popular for plant genome engineering?
a) Affordability
b) Specificity
c) Multiplexing capability
d) Heritability
25. Gene drives could be used for:
a) Eliminating disease vectors like mosquitoes
b) Altering crop traits
c) Releasing invasive species
d) None of the above
26. Regulation of genome editing mainly focuses on:
a) Germline modifications
b) Off-target effects
c) Efficiency
d) Transfection methodology
27. Insertional mutagenesis refers to:
a) Unintended mutations from editing
b) Deliberate integration of transgenes
c) DNA damage during cellular replication
d) Errors in homology directed repair
28. CRISPR-enhanced prime editing makes alterations by:
a) Generating site-specific double-stranded breaks
b) Priming DNA synthesis without cleavage
c) Using shorter guide RNA to find targets
d) All of the above
29. Which type of gene drive self-spreads genetically modified traits:
a) Underdominance
b) Kampo
c) Mutagenic chain
d) Suppression
30. Gene drives need not alter the germline if used:
a) Within a single generation
b) On monocarpic plants
c) In somatic cell gene therapies
d) None of the above
31. TALENs employ a transcription activator-like effector domain fused to:
a) Cas9 protein
b) A nuclease
c) Guide RNA molecules
d) Selectable markers
32. Maternal effect gene drives cause:
a) Altered inheritance through sperm
b) Modifications to breeding populations
c) Genetic changes only in offspring
d) Changes restricted to a single sex
33. Which is an example of genetically modifying plants using CRISPR?
a) Disease resistant rice
b) Low-methionine cocoa beans
c) Salt tolerant wheat
d) All of the above
34. The human germline is altered in:
a) Somatic cell gene therapy
b) Ex vivo gene editing of hematopoietic stem cells
c) Mitochondrial replacement therapy
d) In vivo editing of embryos, eggs or sperm
35. Targeted integration for ex vivo therapies involves:
a) NHEJ pathway only
b) HDR pathway only
c) Both HDR and NHEJ pathways
d) Viral transduction methods
36. A nuclease cuts DNA at the target locus to create:
a) Single stranded breaks
b) Double stranded breaks
c) Insertions
d) Deletions
37. Improving HDR efficiency can utilize:
a) CRISPR-Cas9 only
b) CRISPR-Cas9 and AAV donor vectors
c) ZFNs and donor plasmids
d) TALENs and homology arms
38. Editing haploid cells allows rapid generation of:
a) Transgenic organisms
b) Mice with specific mutations
c) Hybrid cell lines
d) All of the above
39. Therapies that do not alter the human germline are known as:
a) Germline gene editing
b) Mitochondrial replacement
c) Somatic cell gene editing
d) Ex vivo gene therapy
40. Which application is still scientifically controversial and not legal?
a) Treating genetic diseases
b) Enhancing transplant rejection
c) Germline gene editing for enhancement
d) Modifying livestock for agriculture
41. An advantage CRISPR has over other tools is its:
a) Affordability
b) Specificity
c) Multiplexing ability to target several genes at once
d) All of the above
42. Cell lineage tracing uses which type of marker?
a) Transposon
b) Luminescent
c) Constitutive
d) Inducible
43. Precision genome editing aims to address:
a) Off-target effects
b) Mosaicism
c) Permanent changes to the germline
d) All of the above
44. A homology arm is:
a) The DNA-cutting domain of an endonuclease
b) The DNA sequence targeted by a gene editing tool
c) A segment of DNA used to direct repair of the cut site
d) The RNA-guided part of the