 |
MOD621S - MOLECULAR DIAGNOSTICS - 2ND OPP - JANUARY 2025 |
|
|
1 Page 1 |
▲back to top |
nAml BIA un IVERSITY
OF SCIEnCE AnDTECHnOLOGY
Faculty of Health, Natural
Resources and Applied
Sciences
School of Health Sciences
Department of Clinical
Health Sciences
13Jackson Kaujeua Street
Private Bag 13388
Windhoek
NAMIBIA
T: +264 61 207 2970
F: +264 61 207 9970
E: dchs@nust.na
W: www.nust.na
QUALIFICATION: BACHELOR of MEDICAL LABORATORY SCIENCES
QUALIFICATION CODE: 0SBMLS
LEVEL:6
COURSE:MOLECULAR DIAGNOSTICS
COURSECODE: MOD621S
DATE: JANUARY 2025
SESSION: 1
DURATION: 3 HOURS
MARKS: 100
SECOND OPPORTUNITY/ SUPPLEMENTARY: EXAMINATION QUESTION PAPER
EXAMINER:
MODERATOR:
Ms Vanessa Tjijenda
Mrs Roselin Belinda Tsauses
INSTRUCTIONS:
1. Answer all questions on the separate answer sheet.
2. Please write neatly and legibly.
3. Do not use the left side margin of the exam paper. This must be allowed for the
examiner.
4. No books, notes and other additional aids are allowed.
5. Mark all answers clearly with their respective question numbers.
PERMISSIBLE MATERIALS:
1. Non-Programmable Calculator
ATTACHEMENTS
1. None
This question paper consists of 5 pages including this front page.
|
|
2 Page 2 |
▲back to top |
|
|
3 Page 3 |
▲back to top |
SECTION A: TRUE FALSE
14 MARKS
QUESTION 1:
[14 MARKS]
Evaluate the statements and select whether the statement is true or false. Write the word 'True' or
'False' next to the corresponding number on your ANSWERSHEET.
1.1 Loading dye is used in gel electrophoresis to add weight and colour to the DNA.
(1)
1.2 Chloroform is used to prevent foaming during nucleic acid extraction.
(1)
1.3 In preparing 0.8 % agarose gel, 0.8 g agarose is dissolved in 250ml TAE buffer.
(1)
1.4 Fluorescent in situ Hybridization is used to diagnose Philadelphia Chromosome in
leukaemia patients.
(1)
1.5 The detection of novel mutations in a gene is achieved by microarray.
(1)
1.6 NGStechnology that sequence DNA via three basic processes: amplify,
sequencing and analyse using a bridging method is called pyrosequencing.
(1)
1.7 The melting temperature of a primer is calculated using the following formula:
4(G+C)+ 2 (A+T).
(1)
1.8 ACCTAGGTis a palindrome sequence.
(1)
1.9 Lysozyme inactivates nucleases.
(1)
1.10 Short tandem repeats are found in the non-coding region of the DNA in each individual. (1)
1.11 Central Dogma of Molecular Biology includes translation, transcription and reverse
transcription.
(1)
1.12 When choosing a restriction enzyme, blunt sites are optimal for cloning.
(1)
1.13 After 6 cycles of a PCR,64 copies are created.
(1)
1.14 Heparin is the preferred anticoagulant for blood specimen collected for molecular
analysis.
(1)
Molecular Diagnostics (MOD621S)
2nd Opportunity- January 2025
2
|
|
4 Page 4 |
▲back to top |
|
|
5 Page 5 |
▲back to top |
SECTION B: SHORT ANSWER QUESTIONS
Please answer ALL of the questions in this section.
QUESTION 2
2.1 Explain the function of the following enzymes:
2.1.1 RNA polymerase
2.1.2 Proteinase K
2.1.3 T4 PolynucleatideKinase
2.1.4 Taq polymerase
2.1.5 Reverse transcriptase
2.1.6 Type II restriction endonucleases
2.1.7 S1 Nuclease
[SO MARKS]
[12]
(1)
(1)
(1)
(1)
(1)
(1)
(1)
2.2 A baby with Edwards' syndrome has chromosomal abnormality as observed in the
image below. This affects the way the baby grows and develops. This abnormality usually
happens by chance, because of a change in the sperm or egg before a baby is conceived.
12
rJi\\ f;.t i
13
15
16
17
f
19
X
2.2.1 Identify the chromosomal abnormality observed in the image above.
(2)
2.2.2 Which molecular test is performed to identify the abnormality?
(1)
2.2.3 Briefly describe the probes used to detect the abnormality?
(2)
Molecular Diagnostics (MOD621S)
2nd Opportunity- January 2025
3
|
|
6 Page 6 |
▲back to top |
|
|
7 Page 7 |
▲back to top |
QUESTION 3
[20]
3.0 Analyse the case study below and answer the question.
"On August 28, 2022, the Ministry of Health and Social Services was notified by a private hospital
emergency department of a suspected foodborne outbreak. On the previous day, 4 members of a
sports team were admitted to the emergency room with complaints of abdominal pain, nausea,
vomiting, and diarrhoea; all patients reported to have had the same dinner at the same local
restaurant 3 h before. They did not eat together at any other restaurant on the day they became
unwell. Two of these patients needed medical care. From 8.30 to 9.30 p.m., a total of 42 meals were
served and at 11.30 p.m., the first set of customers started manifesting gastrointestinal symptoms.
Microbiological analyses of biological, hand swabs from the food handlers, and food samples were
performed, and an epidemiological investigation was conducted to characterize the outbreak."
Results obtained from the samples analysed from NIP molecular unit are shown below:
1
2
3
4
5
6
7
8
9 lO
- l000bp
=:-1· -700bp
-400bp
- 200bp
-I00bp
Lane 1 is the positive control; Lane 2 is from one of the food handlers sample; lane 3 & 4 is dessert
(cream cheesecake) eaten by the team members; lane 5-7 is from the environmental surfaces; lane
8 & 9 is from the stool samples from the two team members. Lane 10 is the DNA ladder.
3.1 Explain the principle of Polymerase Chain Reaction.
(2)
3.2 Identify and describe the reagents that form part of a "master mix" in a qPCRand their
function.
(10)
3.2 Discussthe results from the laboratory in relation to the report above.
(8)
Molecular Diagnostics (MOD6215)
2nd Opportunity- January 2025
4
|
|
8 Page 8 |
▲back to top |
|
|
9 Page 9 |
▲back to top |
QUESTION 4:
4.0 Tabulate Northern, Southern and Western blot techniques based on:
4.1 Sample type
4.2 Probe used
4.3 Gel type
4.4
Detection method
4.5 Principle
[18)
(3)
(3)
(3)
(3)
(6)
;SECTIONB: LONG ANSWER QUESTIONS
Please answer ALL of the questions in this section.
(36 MARKS)
QUESTION 5:
5.1 Microarray is a technique used for gene expression profiling. Discuss in detail the
principle of this technique and mention one advantage and one disadvantage of
using this method.
(10)
5.2 Nested PCRand Touch Down PCRare Conventional PCRmethod that can be modified
to increase specificity. Explain how specificity is achieved in each method.
(16)
5.3 Explain the steps involved in Pyrosequencing in the correct order.
(10)
END OF QUESTIONPAPER
Molecular Diagnostics (MOD621S)
2nd Opportunity- January 2025
5
|
|
10 Page 10 |
▲back to top |
