Molecular Diagnostics Practice
Comprehensive Resource To Help You Ace 2026-2027 Exams
Includes Frequently Tested Questions With ELABORATED
100% Correct COMPLETE SOLUTIONS
Guaranteed Pass First Attempt!! Current Update!!
1. What action should be taken if an unlabeled collection tube with a requisition for a
factor V Leiden test is received in the laboratory. - Correct Answer: Notify the
supervisor and reject the specimen.
2. What action should be taken if after PCR, the amplification control has failed to yield a
product? - Correct Answer: Check the original DNA or RNA preparation. If it is
adequate, repeat the amplification. If not, reisolate the nucleic acid.
3. What action should be taken if an isolated DNA sample is to be stored for at least 6
months? - Correct Answer: Store at -70 degrees C in a tightly sealed tube.
4. What action should be taken if a bone marrow specimen arrives at the end of a shift and
will not be processed for the BCL-2 translocation until the next day? - Correct
Answer: Place the specimen in the refrigerator
5. What action should be taken if the temperature of a refrigerator set at 8 degrees C (+/- 2
degrees C) reads 14 degrees C? - Correct Answer: Recheck the temperature after a
few hours. If it does not return to range, notify the supervisor.
6. What action should be taken if a PCR test for BCR/ABL translocation was negative for the
patient sample and for the sensitivity control? - Correct Answer: Repeat the PCR
with the addition of a new sensitivity control
,7. What action should be taken if a fragile X result has been properly reviewed and
reported? - Correct Answer: File the test results, documents, and associated
autoradiographs together in the laboratory archives
8. What action should be taken if a bottle of reagent alcohol with a 3 in the red diamond
on its label is to be stored? - Correct Answer: Place the alcohol bottle in a safety
storage cabinet for flammable liquids.
9. What action should be taken if the expiration date on a reagent has passed? -
Correct Answer: Discard the reagent. If it can be used for nonclinical purposes, label and
store it in a separate area away from patient testing reagents.
10. What action should be taken if the test results are to be faxed to the ordering physician?
- Correct Answer: Fax the results with a cover sheet containing the proper
disclaimers.
11. What action should be taken if among a group of properly labeled containers, there is a
container similar to the others, but unlabeled? - Correct Answer: Do not use the
material in the unlabeled container. Consult the institutional safety representative for
proper disposal of the contents.
12. What action should be taken if a blood sample is received in a serum tube for PML-RARA
testing by PCR? - Correct Answer: Notify the supervisor that the specimen cannot be
tested and explain the collection error (wrong/no anticoagulant)
13. What action should be taken if the laboratory is reporting a gene mutation replacing
glycine at position 215 with alanine. The results are written 215G --> A in the test report.
- Correct Answer: Correct the test report to A215G before verification by the
laboratory director.
,14. What action should be taken if a test result falls outside of the analytical measurement
range of the validated method? - Correct Answer: If the result exceeds the range,
dilute the specimen and retest. If the results are below the range, report the results as
less than the lower limit of the assay.
15. What action should be taken if a reference standard is read at higher than their
designated concentrations? - Correct Answer: Calibrate the instrument/detection
system using the reference standards.
16. What action should be taken if a new FDA-approved test does not perform as expected?
- Correct Answer: Do not use the test. Contact the manufacturer. Consider an
alternate test system.
17. What action should be taken if the laser on a complex instrument malfunctions? -
Correct Answer: Call the instrument manufacturer. Do not try to access the laser.
18. What action should be taken if a solution containing radioactive waste has been stored
in a properly protected area for 10 half-lives of the isotope? - Correct Answer: The
solution may be safely discarded; however, contact the institutional safety department
before discarding. Document all radioactive waste disposal.
19. What action should be taken if there is no available proficiency test for a new method
developed in the laboratory? - Correct Answer: Establish an agreement with another
laboratory to trade samples for testing. Use split samples from reference standards.
Compare results with a reference in-house method, regional pools, previously assayed
material, clinical evaluation, or other documented means
20. What action should be taken if a research investigator asks for a patient specimen? -
Correct Answer: Notify the supervisor. Do not release patient material without proper
consent and patient safety review board approval
, 21. Which of the following is a high-resolution HLA typing result?
a) B27
b) A*02:02-02:09
c) A*02:12
d) A*26:01/A*26:05/A*26:01/A*26:15 - Correct Answer: C) A*02:12. A*02
would be low resolution, determined at the serological level.
A*26:01/A*26:05/A*26:01/A*26:15 is a medium resolution result.
22. Which of the following is a likely haplotype from parents with A25, Cw10, B27/A23, Cw5,
B27 and A17, Cw4,B10/A9, Cw7,B12 haplotypes?
a) A25, Cw10, B27
b) A25, Cw5, B27
c) A23, Cw4, B12
d) A17, Cw4, B27 - Correct Answer: A) A25, Cw10, B27 would be inherited
together from one parent. A25,Cw5. B27 may occur as a result of a
recombination even, but would be infrequent.
23. Upon microscopic examination, over 90% of cells are translucent after a CDC assay. How
are these results scored according to the ASHI rules? - Correct Answer: Negative for
the presence of the test antigen or a score of 1. Less than 10% of the cells have taken up
dye. Cytotoxicity (dye uptake) will only occur in those cells that carry antigens to the test
antibodies.
24. A theoretical HLA-A*02 allele is a CTC to CTT change at the DNA level (leu --> leu). How is
this allele written?
a) HLA-A*02:01
b) HLA-A*02:01:01
c) HLA-A2
d) HLA-A*02N - Correct Answer: B) Nucleotide substitutions that change the
amino acid sequence are indicated by differences in the second group of digits.
Those changes in the DNA sequence that do not change the amino acid
sequenece (silent or synonymous substitutions) are designated by addition of a
third group of digits.
Comprehensive Resource To Help You Ace 2026-2027 Exams
Includes Frequently Tested Questions With ELABORATED
100% Correct COMPLETE SOLUTIONS
Guaranteed Pass First Attempt!! Current Update!!
1. What action should be taken if an unlabeled collection tube with a requisition for a
factor V Leiden test is received in the laboratory. - Correct Answer: Notify the
supervisor and reject the specimen.
2. What action should be taken if after PCR, the amplification control has failed to yield a
product? - Correct Answer: Check the original DNA or RNA preparation. If it is
adequate, repeat the amplification. If not, reisolate the nucleic acid.
3. What action should be taken if an isolated DNA sample is to be stored for at least 6
months? - Correct Answer: Store at -70 degrees C in a tightly sealed tube.
4. What action should be taken if a bone marrow specimen arrives at the end of a shift and
will not be processed for the BCL-2 translocation until the next day? - Correct
Answer: Place the specimen in the refrigerator
5. What action should be taken if the temperature of a refrigerator set at 8 degrees C (+/- 2
degrees C) reads 14 degrees C? - Correct Answer: Recheck the temperature after a
few hours. If it does not return to range, notify the supervisor.
6. What action should be taken if a PCR test for BCR/ABL translocation was negative for the
patient sample and for the sensitivity control? - Correct Answer: Repeat the PCR
with the addition of a new sensitivity control
,7. What action should be taken if a fragile X result has been properly reviewed and
reported? - Correct Answer: File the test results, documents, and associated
autoradiographs together in the laboratory archives
8. What action should be taken if a bottle of reagent alcohol with a 3 in the red diamond
on its label is to be stored? - Correct Answer: Place the alcohol bottle in a safety
storage cabinet for flammable liquids.
9. What action should be taken if the expiration date on a reagent has passed? -
Correct Answer: Discard the reagent. If it can be used for nonclinical purposes, label and
store it in a separate area away from patient testing reagents.
10. What action should be taken if the test results are to be faxed to the ordering physician?
- Correct Answer: Fax the results with a cover sheet containing the proper
disclaimers.
11. What action should be taken if among a group of properly labeled containers, there is a
container similar to the others, but unlabeled? - Correct Answer: Do not use the
material in the unlabeled container. Consult the institutional safety representative for
proper disposal of the contents.
12. What action should be taken if a blood sample is received in a serum tube for PML-RARA
testing by PCR? - Correct Answer: Notify the supervisor that the specimen cannot be
tested and explain the collection error (wrong/no anticoagulant)
13. What action should be taken if the laboratory is reporting a gene mutation replacing
glycine at position 215 with alanine. The results are written 215G --> A in the test report.
- Correct Answer: Correct the test report to A215G before verification by the
laboratory director.
,14. What action should be taken if a test result falls outside of the analytical measurement
range of the validated method? - Correct Answer: If the result exceeds the range,
dilute the specimen and retest. If the results are below the range, report the results as
less than the lower limit of the assay.
15. What action should be taken if a reference standard is read at higher than their
designated concentrations? - Correct Answer: Calibrate the instrument/detection
system using the reference standards.
16. What action should be taken if a new FDA-approved test does not perform as expected?
- Correct Answer: Do not use the test. Contact the manufacturer. Consider an
alternate test system.
17. What action should be taken if the laser on a complex instrument malfunctions? -
Correct Answer: Call the instrument manufacturer. Do not try to access the laser.
18. What action should be taken if a solution containing radioactive waste has been stored
in a properly protected area for 10 half-lives of the isotope? - Correct Answer: The
solution may be safely discarded; however, contact the institutional safety department
before discarding. Document all radioactive waste disposal.
19. What action should be taken if there is no available proficiency test for a new method
developed in the laboratory? - Correct Answer: Establish an agreement with another
laboratory to trade samples for testing. Use split samples from reference standards.
Compare results with a reference in-house method, regional pools, previously assayed
material, clinical evaluation, or other documented means
20. What action should be taken if a research investigator asks for a patient specimen? -
Correct Answer: Notify the supervisor. Do not release patient material without proper
consent and patient safety review board approval
, 21. Which of the following is a high-resolution HLA typing result?
a) B27
b) A*02:02-02:09
c) A*02:12
d) A*26:01/A*26:05/A*26:01/A*26:15 - Correct Answer: C) A*02:12. A*02
would be low resolution, determined at the serological level.
A*26:01/A*26:05/A*26:01/A*26:15 is a medium resolution result.
22. Which of the following is a likely haplotype from parents with A25, Cw10, B27/A23, Cw5,
B27 and A17, Cw4,B10/A9, Cw7,B12 haplotypes?
a) A25, Cw10, B27
b) A25, Cw5, B27
c) A23, Cw4, B12
d) A17, Cw4, B27 - Correct Answer: A) A25, Cw10, B27 would be inherited
together from one parent. A25,Cw5. B27 may occur as a result of a
recombination even, but would be infrequent.
23. Upon microscopic examination, over 90% of cells are translucent after a CDC assay. How
are these results scored according to the ASHI rules? - Correct Answer: Negative for
the presence of the test antigen or a score of 1. Less than 10% of the cells have taken up
dye. Cytotoxicity (dye uptake) will only occur in those cells that carry antigens to the test
antibodies.
24. A theoretical HLA-A*02 allele is a CTC to CTT change at the DNA level (leu --> leu). How is
this allele written?
a) HLA-A*02:01
b) HLA-A*02:01:01
c) HLA-A2
d) HLA-A*02N - Correct Answer: B) Nucleotide substitutions that change the
amino acid sequence are indicated by differences in the second group of digits.
Those changes in the DNA sequence that do not change the amino acid
sequenece (silent or synonymous substitutions) are designated by addition of a
third group of digits.
