Deck 35: Molecular Diagnostic Techniques in Hematopathology

Question 1

Which structures serve as templates for RNA transcription and protein translation?

A) Lipids
B) Amino acids
C) Genes
D) Ribonucleotides

Answer 1

Genes

Question 2

DNA extracted from fresh cells or frozen tissue is resuspended in buffer and can be stored indefinitely at what temperature prior to amplification?

A) 0°C
B) 4°C
C) 20°C
D) -20°C
E) -10°C

Answer 2

-20°C

Question 3

A probe binds to its target through a process called _______________________.

A) Transcription
B) Hybridization
C) Neutralization
D) Translation
E) None of the above

Answer 3

Hybridization

Question 4

Intact DNA is usually well preserved in tissues that are frozen within what time after collection?

A) 1 hour
B) 6 hours
C) 12 hours
D) 24 hours
E) 48 hours

Question 5

Which of the following hematopoietic cancer(s) have known oncogenes related to them?

A) Chronic myelogenous leukemia
B) Acute lymphoblastic leukemia
C) Burkitt lymphoma
D) T-cell leukemia
E) All of the above

Question 6

DNA and RNA are quantitated spectrophotometrically because nucleic acids absorb ultraviolet light at what optical density?

A) 200 nm
B) 260 nm
C) 280 nm
D) 320 nm
E) 400 nm

Question 7

A gene whose alteration is responsible for cancer formation is called a(n) _________.

A) Heavy chain gene
B) Oncogene
C) Light chain gene
D) Pseudogene
E) None of the above

Question 8

Which of the following enzymes are most commonly used for sequence-specific cleavage of DNA?

A) EcoR1
B) BamH1
C) HindIII
D) All of the above
E) None of the above

Question 9

DNA extracted from fresh cells or frozen tissue is resuspended in buffer and can be stored at 4°C for how long prior to amplification?

A) 6 hours
B) 24 hours
C) 7 days
D) 14 days
E) 1 month

Question 10

Which of the following specimen criteria is best for DNA analysis by the Southern blot method?

A) A tissue fixed in ethanol within 2 hours of collection
B) A tissue that is frozen within 48 hours of collection
C) A blood sample that is 5 days old
D) A tissue fixed in formaldehyde within 1 hour of collection
E) None of the above

Question 11

Human DNA is packaged into how many chromosomes?

A) 46
B) 23
C) 26
D) 50

Question 12

Which of the following is/are true regarding "probes"?

A) Help to identify a specific RNA nucleotide sequence.
B) Help to identify a specific DNA nucleotide sequence.
C) Follow the rules of complementary nucleotide pairing.
D) All of the above.

Question 13

Which of the following statements describe a probe as used in molecular diagnostics?

A) A single-stranded segment of nucleic acid (either DNA or RNA) whose nucleotide sequence is complementary to a target sequence (either DNA or RNA).
B) A double-stranded segment of nucleic acid (either DNA or RNA) whose nucleotide sequence is complementary to a target sequence (either DNA or RNA).
C) A single-stranded segment of amino acids encoded by a target sequence (either DNA or RNA).
D) All of the above.

Question 14

In complementary nucleotide pairing, an adenine can bind only with __________________ and guanine can bind only with _________.

A) Cytosine, thymine
B) Thymine, cytosine
C) Guanine, adenine
D) Glucine, thymine

Question 15

Which of the following describes the reason why RNA is unstable?

A) It is single-stranded.
B) It is easily degraded by ubiquitous natural enzymes collectively termed RNase.
C) The sugar ribose gives RNA an unstable structure.
D) The nucleotide uracil gives RNA an unstable structure.
E) None of the above

Question 16

Naturally occurring enzymes that chop DNA into small fragments are called ________________________.

A) RNases
B) Protease
C) Nucleotidases
D) Restriction endonucleases
E) None of the above

Question 17

Which substance acts as an intermediary to DNA in transmitting genetic information?

A) Oncogenes
B) Chromosomes
C) RNA (ribonucleic acid)
D) Nucleotides

Question 18

Intact DNA is usually well preserved in blood samples that are less than how many days old?

A) 10 days
B) 7 days
C) 6 days
D) 4 days
E) 2 days

Question 19

DNA or RNA is readily extracted from which of the following specimens?

A) Blood
B) Marrow
C) Body fluid cells
D) Tissue samples
E) All of the above

Question 20

Which statement is true regarding genomic DNA extraction from blood?

A) Only the cell membranes are represented.
B) Only the cytoplasm is represented.
C) Only the mature red cells are represented.
D) Only the nucleated cell fraction is represented.

Question 21

Which of the following is/are major advantages of PCR?

A) Extremely sensitive to low numbers of target sequences
B) Small sample size requirements
C) Relatively fast and inexpensive unless extensive post-amplification analysis is required
D) Permits analysis of formalin-fixed, paraffin-embedded tissue that is not suitable for Southern blot analysis
E) All of the above

Question 22

Which of the following is the major disadvantage of RT-PCR?

A) DNA is labile and therefore all DNA-based testing require meticulous care to avoid degradation.
B) Large sample size is required.
C) Not sensitive to low number of target sequences.
D) RNA is labile and therefore all RNA-based testing requires meticulous care to avoid degradation by RNases.
E) All of the above

Question 23

Which of the following is/are clinical application(s) of RT-PCR?

A) Determine expression of selected genes by targeting their corresponding RNA transcripts
B) Detect certain disease-specific chromosomal translocations where RNA is transcribed across the translocation breakpoint
C) Detect minimal residual disease in cancer patients following therapy by amplifying tumor-specific fusion transcripts
D) Detect foreign organisms using probes targeting abundantly transcribed sequences or targeting viruses having RNA genomes
E) All of the above

Question 24

Which of the following methods can amplify particular segments of target DNA a billion-fold?

A) Restriction fragment length polymorphism (RFLP)
B) Southern blot
C) Polymerase chain reaction (PCR)
D) Western blot
E) None of the above

Question 25

Which of the following describes a procedural step in reverse transcriptase polymerase chain reaction (RT-PCR)?

A) RNA is converted to complementary DNA (cDNA) using the enzyme reverse transcriptase
B) DNA is amplified using reverse transcriptase enzyme
C) RNA is cut into smaller fragments using the enzyme reverse transcriptase
D) None of the above
E) All of the above

Question 26

Which anticoagulant is preferred for diagnostic procedures that analyze DNA since it does not inhibit the action of restriction endonucleases?

A) Heparin
B) Sodium fluoride (NAFl)
C) Ethylenediaminetetraacetic acid (EDTA)
D) Calcium oxalate
E) None of the above

Question 27

Which of the following is/are clinical applications of PCR?

A) Detect foreign nucleic acid characteristic of infectious diseases
B) Detect DNA that has a particular cancer-associated defect
C) Detect minimal residual disease
D) Detect clonal immunoglobulin or T-cell receptor gene rearrangement
E) All of the above

Question 28

Which of the following diagnostic procedures for analyzing DNA is the most accurate method for detecting gene rearrangements in lymphoid leukemias and lymphomas?

A) Southern blot analysis
B) Northern blot analysis
C) Western blot analysis
D) Eastern blot analysis
E) None of the above

Question 29

Which of the following are clinical applications of in situ hybridization to cells or tissues immobilized on glass slides?

A) Determine the disease related location of foreign organisms
B) Detect and localize gene expression by targeting RNA transcripts
C) Detect point mutations such as the sickle cell anemia mutation
D) A and B
E) All of the above

Question 30

Which of the following is the major disadvantage of PCR?

A) Extremely sensitive to low numbers of target sequences
B) Extreme precautions are required to avoid contamination of samples or reagents by extraneous DNA
C) Relatively slow and expensive
D) Requires a large sample size
E) All of the above

Question 31

The restriction endonuclease HindIII is derived from which of the following organisms?

A) Escherichia coli
B) Bacillus amyloliquifaciens
C) Haemophilus influenzae
D) Streptococcus pneumoniae
E) Staphylococcus aureus

Question 32

Which of the following is/are probe label(s)?

A) Radioisotopes
B) Biotin
C) Digoxigenin
D) All of the above
E) None of the above

Question 33

Some individuals use the term "restriction fragment length polymorphism (RFLP)" as a synonym for what method of detecting genetic alterations?

A) Northern blot
B) Southern blot
C) Western blot
D) Eastern blot
E) None of the above

Question 34

What is the major advantage of fluorescence in situ hybridization (FISH)?

A) Permits visualization of target DNA in the context of karyotypic visualization of metaphase chromosomes
B) Requires live cells capable of entering mitosis to interpret results in interphase chromosomes
C) Visualization of fluorochrome requires input light source
D) All of the above
E) None of the above