ABPath CertLinkMolecular Genetic Pathology Practice Exam
Question 1: What does the central dogma of molecular genetics describe?
A. DNA replication to protein synthesis
B. DNA transcription to RNA translation
C. RNA replication to DNA translation
D. Protein transcription to DNA replication
Answer: B
Explanation: The central dogma explains that genetic information flows from DNA to RNA to protein.
Question 2: Which component is the basic structural unit of a gene?
A. Promoter region
B. Exon
C. Intron
D. Enhancer
Answer: B
Explanation: Exons are the coding regions that are expressed in the final mRNA product.
Question 3: What type of mutation involves the replacement of a single nucleotide?
A. Frameshift mutation
B. Deletion mutation
C. Missense mutation
D. Nonsense mutation
Answer: C
Explanation: A missense mutation changes one nucleotide, altering one amino acid in the protein
sequence.
Question 4: Which process is used to amplify a specific DNA segment?
A. Gel electrophoresis
B. Polymerase Chain Reaction (PCR)
C. Southern blotting
D. Next-generation sequencing
Answer: B
Explanation: PCR is a technique used to exponentially amplify a specific segment of DNA.
Question 5: What is the primary purpose of gel electrophoresis?
A. To sequence DNA
B. To separate DNA fragments by size
C. To clone genes
D. To transcribe RNA
Answer: B
Explanation: Gel electrophoresis separates DNA fragments based on size and charge.
Question 6: Which method allows detection of specific DNA sequences on a membrane?
A. PCR
B. Microarrays
C. Southern blotting
,D. CRISPR-Cas9
Answer: C
Explanation: Southern blotting transfers DNA fragments from a gel to a membrane for hybridization with
probes.
Question 7: What does next-generation sequencing (NGS) primarily enable?
A. Cloning of large DNA fragments
B. High-throughput DNA sequencing
C. Isolation of proteins
D. Simple PCR amplification
Answer: B
Explanation: NGS allows rapid, large-scale sequencing of entire genomes or targeted regions.
Question 8: Which technique uses fluorescent probes to localize specific DNA sequences within cells?
A. FISH
B. LAMP
C. PCR
D. Western blotting
Answer: A
Explanation: Fluorescence in situ hybridization (FISH) uses fluorescent probes to detect and localize DNA
sequences on chromosomes.
Question 9: What is a key feature of CRISPR-Cas9 technology?
A. It sequences RNA directly.
B. It amplifies DNA segments.
C. It enables targeted gene editing.
D. It separates proteins by size.
Answer: C
Explanation: CRISPR-Cas9 is a genome editing tool that can introduce specific modifications in DNA.
Question 10: In gene expression, what is the function of a promoter?
A. To terminate transcription
B. To bind transcription factors and initiate transcription
C. To splice mRNA
D. To modify proteins post-translation
Answer: B
Explanation: Promoters are DNA sequences that bind transcription factors, initiating RNA polymerase
activity and transcription.
Question 11: Which statement best defines genetic variation?
A. The process of DNA replication
B. The differences in DNA sequences among individuals
C. The transcription of RNA from DNA
D. The process of protein synthesis
Answer: B
Explanation: Genetic variation refers to the differences in the nucleotide sequences among individuals.
,Question 12: What is a chromosomal abnormality involving an extra chromosome called?
A. Deletion
B. Translocation
C. Duplication
D. Trisomy
Answer: D
Explanation: Trisomy is a numerical chromosomal abnormality where an extra copy of a chromosome is
present.
Question 13: Which mechanism is essential for gene regulation at the transcriptional level?
A. Protein folding
B. DNA methylation
C. RNA splicing
D. Chromatin remodeling
Answer: D
Explanation: Chromatin remodeling changes DNA accessibility for transcription factors, thus regulating
gene expression.
Question 14: What does the term “epigenetics” refer to?
A. DNA mutations only
B. Heritable changes in gene function that do not involve changes to the DNA sequence
C. RNA sequence alterations
D. Protein synthesis errors
Answer: B
Explanation: Epigenetics involves modifications, such as methylation and histone modification, that
affect gene expression without altering the DNA sequence.
Question 15: Which of the following is NOT a step in PCR?
A. Denaturation
B. Annealing
C. Extension
D. Hybridization blotting
Answer: D
Explanation: PCR involves denaturation, annealing, and extension; hybridization blotting is part of
Southern blotting, not PCR.
Question 16: What role does reverse transcriptase play in molecular diagnostics?
A. Amplifies DNA segments
B. Converts RNA into complementary DNA (cDNA)
C. Separates proteins
D. Digests DNA
Answer: B
Explanation: Reverse transcriptase synthesizes complementary DNA from an RNA template.
Question 17: In molecular genetics, what is the significance of single nucleotide polymorphisms
(SNPs)?
A. They cause large chromosomal rearrangements
, B. They are the most common type of genetic variation
C. They eliminate gene expression
D. They only occur in non-coding regions
Answer: B
Explanation: SNPs are single base-pair variations in the genome and are the most common form of
genetic variation.
Question 18: Which technique is primarily used for gene expression profiling on a large scale?
A. PCR
B. Microarrays
C. Gel electrophoresis
D. CRISPR-Cas9
Answer: B
Explanation: Microarrays allow simultaneous measurement of the expression levels of thousands of
genes.
Question 19: How does fluorescence in situ hybridization (FISH) help in diagnosing genetic
abnormalities?
A. By amplifying DNA
B. By directly visualizing gene location and copy number on chromosomes
C. By sequencing DNA
D. By editing the genome
Answer: B
Explanation: FISH uses fluorescent probes to detect and localize specific DNA sequences, identifying
chromosomal abnormalities.
Question 20: Which principle underlies the design of gene expression microarrays?
A. Hybridization between complementary nucleic acids
B. Enzymatic digestion of proteins
C. Amplification of RNA by PCR
D. Direct visualization of chromosomes
Answer: A
Explanation: Microarrays rely on the hybridization of labeled nucleic acids to complementary probes
fixed on a surface.
Question 21: What is the main goal of molecular diagnostics in oncology?
A. To amplify any DNA sequence
B. To detect and interpret genetic alterations that drive cancer
C. To create synthetic proteins
D. To separate RNA fragments
Answer: B
Explanation: Molecular diagnostics in oncology focuses on identifying genetic mutations and alterations
that contribute to cancer development.
Question 22: Which gene type, when mutated, is most often associated with the development of
cancer?
A. Housekeeping genes
Question 1: What does the central dogma of molecular genetics describe?
A. DNA replication to protein synthesis
B. DNA transcription to RNA translation
C. RNA replication to DNA translation
D. Protein transcription to DNA replication
Answer: B
Explanation: The central dogma explains that genetic information flows from DNA to RNA to protein.
Question 2: Which component is the basic structural unit of a gene?
A. Promoter region
B. Exon
C. Intron
D. Enhancer
Answer: B
Explanation: Exons are the coding regions that are expressed in the final mRNA product.
Question 3: What type of mutation involves the replacement of a single nucleotide?
A. Frameshift mutation
B. Deletion mutation
C. Missense mutation
D. Nonsense mutation
Answer: C
Explanation: A missense mutation changes one nucleotide, altering one amino acid in the protein
sequence.
Question 4: Which process is used to amplify a specific DNA segment?
A. Gel electrophoresis
B. Polymerase Chain Reaction (PCR)
C. Southern blotting
D. Next-generation sequencing
Answer: B
Explanation: PCR is a technique used to exponentially amplify a specific segment of DNA.
Question 5: What is the primary purpose of gel electrophoresis?
A. To sequence DNA
B. To separate DNA fragments by size
C. To clone genes
D. To transcribe RNA
Answer: B
Explanation: Gel electrophoresis separates DNA fragments based on size and charge.
Question 6: Which method allows detection of specific DNA sequences on a membrane?
A. PCR
B. Microarrays
C. Southern blotting
,D. CRISPR-Cas9
Answer: C
Explanation: Southern blotting transfers DNA fragments from a gel to a membrane for hybridization with
probes.
Question 7: What does next-generation sequencing (NGS) primarily enable?
A. Cloning of large DNA fragments
B. High-throughput DNA sequencing
C. Isolation of proteins
D. Simple PCR amplification
Answer: B
Explanation: NGS allows rapid, large-scale sequencing of entire genomes or targeted regions.
Question 8: Which technique uses fluorescent probes to localize specific DNA sequences within cells?
A. FISH
B. LAMP
C. PCR
D. Western blotting
Answer: A
Explanation: Fluorescence in situ hybridization (FISH) uses fluorescent probes to detect and localize DNA
sequences on chromosomes.
Question 9: What is a key feature of CRISPR-Cas9 technology?
A. It sequences RNA directly.
B. It amplifies DNA segments.
C. It enables targeted gene editing.
D. It separates proteins by size.
Answer: C
Explanation: CRISPR-Cas9 is a genome editing tool that can introduce specific modifications in DNA.
Question 10: In gene expression, what is the function of a promoter?
A. To terminate transcription
B. To bind transcription factors and initiate transcription
C. To splice mRNA
D. To modify proteins post-translation
Answer: B
Explanation: Promoters are DNA sequences that bind transcription factors, initiating RNA polymerase
activity and transcription.
Question 11: Which statement best defines genetic variation?
A. The process of DNA replication
B. The differences in DNA sequences among individuals
C. The transcription of RNA from DNA
D. The process of protein synthesis
Answer: B
Explanation: Genetic variation refers to the differences in the nucleotide sequences among individuals.
,Question 12: What is a chromosomal abnormality involving an extra chromosome called?
A. Deletion
B. Translocation
C. Duplication
D. Trisomy
Answer: D
Explanation: Trisomy is a numerical chromosomal abnormality where an extra copy of a chromosome is
present.
Question 13: Which mechanism is essential for gene regulation at the transcriptional level?
A. Protein folding
B. DNA methylation
C. RNA splicing
D. Chromatin remodeling
Answer: D
Explanation: Chromatin remodeling changes DNA accessibility for transcription factors, thus regulating
gene expression.
Question 14: What does the term “epigenetics” refer to?
A. DNA mutations only
B. Heritable changes in gene function that do not involve changes to the DNA sequence
C. RNA sequence alterations
D. Protein synthesis errors
Answer: B
Explanation: Epigenetics involves modifications, such as methylation and histone modification, that
affect gene expression without altering the DNA sequence.
Question 15: Which of the following is NOT a step in PCR?
A. Denaturation
B. Annealing
C. Extension
D. Hybridization blotting
Answer: D
Explanation: PCR involves denaturation, annealing, and extension; hybridization blotting is part of
Southern blotting, not PCR.
Question 16: What role does reverse transcriptase play in molecular diagnostics?
A. Amplifies DNA segments
B. Converts RNA into complementary DNA (cDNA)
C. Separates proteins
D. Digests DNA
Answer: B
Explanation: Reverse transcriptase synthesizes complementary DNA from an RNA template.
Question 17: In molecular genetics, what is the significance of single nucleotide polymorphisms
(SNPs)?
A. They cause large chromosomal rearrangements
, B. They are the most common type of genetic variation
C. They eliminate gene expression
D. They only occur in non-coding regions
Answer: B
Explanation: SNPs are single base-pair variations in the genome and are the most common form of
genetic variation.
Question 18: Which technique is primarily used for gene expression profiling on a large scale?
A. PCR
B. Microarrays
C. Gel electrophoresis
D. CRISPR-Cas9
Answer: B
Explanation: Microarrays allow simultaneous measurement of the expression levels of thousands of
genes.
Question 19: How does fluorescence in situ hybridization (FISH) help in diagnosing genetic
abnormalities?
A. By amplifying DNA
B. By directly visualizing gene location and copy number on chromosomes
C. By sequencing DNA
D. By editing the genome
Answer: B
Explanation: FISH uses fluorescent probes to detect and localize specific DNA sequences, identifying
chromosomal abnormalities.
Question 20: Which principle underlies the design of gene expression microarrays?
A. Hybridization between complementary nucleic acids
B. Enzymatic digestion of proteins
C. Amplification of RNA by PCR
D. Direct visualization of chromosomes
Answer: A
Explanation: Microarrays rely on the hybridization of labeled nucleic acids to complementary probes
fixed on a surface.
Question 21: What is the main goal of molecular diagnostics in oncology?
A. To amplify any DNA sequence
B. To detect and interpret genetic alterations that drive cancer
C. To create synthetic proteins
D. To separate RNA fragments
Answer: B
Explanation: Molecular diagnostics in oncology focuses on identifying genetic mutations and alterations
that contribute to cancer development.
Question 22: Which gene type, when mutated, is most often associated with the development of
cancer?
A. Housekeeping genes
