Closed book
1. Which mode of inheritance is not consistent with the following pedigree chart?
(a) autosomal recessive with high population frequency (b) autosomal dominant with reduced penetrance (c) X-linked recessive with full penetrance (d) X-linked dominant with full penetrance
2. The person indicated by the arrow is a cystic fibrosis (CF) patient with mutations in the CFTR gene.
His mother’s brother and his partner are expecting a child. The couple would like to know this child’s risk for CF. The carriership frequency of CF in the general population is 1 in 30.
What is the probability that the child will have CF?
(a) 1 in 60 (b) 1 in 120 (c) 1 in 180 (d) 1 in 240
3. The pedigree chart below shows a family with hereditary chronic pancreatitis. The penetrance of hereditary pancreatitis is about 80%. The person indicated by the arrow would like to know how likely it is that he will develop chronic pancreatitis.
To determine this risk, assume a mode of inheritance that is most consistent with the chart.
What is the probability that this person will develop chronic pancreatitis?
(a) 12.5%
(b) 40%
(c) 80%
4. When a child with autosomal recessive inherited cystic fibrosis (CF) is born into a family, the probability that the child’s healthy siblings are carriers of the hereditary predisposition for CF is:
(a) 0 (b) 1 in 4 (c) 2 in 3 (d) 3 in 4
5. A baby is born after 39 weeks of pregnancy. Prenatal genetic testing revealed a trisomy. The baby has a second little finger (postaxial polydactyly) and a skin lesion on the crown of his head (aplasia cutis congenita). Birth weight is normal.
Which chromosomal aberration is the most likely, given the above information?
(a) trisomy 21, Down’s syndrome (b) trisomy 18, Edwards syndrome (c) trisomy X, triple X syndrome (d) trisomy 13, Patau syndrome
6. In a child with a genetic defect (causing severe intellectual disability and congenital disorders), the micro-array analysis shows no DNA gain or loss, but it does show two identical copies of the same chromosome 7.
What is the most likely explanation of this child’s condition?
(a) isochromosome formation (b) uniparental disomy (c) mitotic nondisjunction (d) chromosome methylation
7. The risk of having a child with Down’s syndrome increases with the mother’s age. This is caused by a higher probability of meiosis error (non-disjunction) in older mothers. A man can also have meiosis errors, resulting in a genetic disorder in his children.
Which of the following conditions more often develops due to a meiosis error in the father than in the mother?
(a) Turner syndrome (b) Klinefelter’s syndrome (c) trisomy X syndrome (d) Edwards syndrome
8. Hereditary bowel cancer may be caused by pathogenic mutations in several genes. From the phenotypical perspective, it does not matter which gene was affected by the pathogenic mutation.
What is the name of this phenomenon within genetics?
(a) pleiotropy
(b) locus heterogeneity (c) variable expression
9. Which technique is used in a DNA diagnostic laboratory to detect point mutations?
(a) array CGH (b) DNA sequencing (c) karyotyping (d) FISH
10. Which mode of inheritance is most consistent with the pedigree chart below?
(a) X-linked recessive pattern (b) autosomal dominant (c) Y-linked
(d) mitochondrial
11. Most children with spina bifida have hydrocephalus, which is caused by:
(a) meningeal inflammation
(b) excessive loss of CSF via the non-closed backbone (c) blockage of CSF circulation in the cerebellum (d) excessive production of CSF in the ventricles
12. If a women takes extra folic acid during pregnancy, she reduces the risk of her foetus developing spina bifida.
It is recommended that she takes this extra folic acid:
(a) starting one year before conception to/until the 20th week of pregnancy (b) from at least 4 weeks before conception to/until the 8th week of pregnancy (c) for 3 months immediately after pregnancy has been confirmed
(d) during the entire pregnancy
13.
The above figure shows a cross section of an embryo.
In which plane was this cut made?
(a) axial (b) frontal (c) sagittal (d) transverse
14.
Which anatomical structure develops from the embryonic tissue indicated by the arrow in the above figure?
(a) kidneys (b) heart
(c) intervertebral discs (d) stomach
15. Which structure induces the development of the neural plate?
(a) hypoblast (b) neural fold
(c) notochord (chorda dorsalis) (d) primitive streak
16. Which space in the above image will develop into the lumen of the gastrointestinal tract?
(a) space 1 (b) space 2 (c) space 3 (d) space 4
17. A cell is permeable for a monovalent cation X. The extracellular concentration of this ion is ten times higher than its intracellular concentration.
What is the equilibrium potential (Nernst potential)?
It is closest to:
(a) -30 mV (b) 30 mV (c) -60 mV (d) 60 mV
18. Which of the following proteins displays ATPase activity?
(a) actin (b) myosin (c) titin
(d) tropomyosin
19. ATP plays an important role in muscle contractions.
Which process requires ATP?
(a) exposure of the binding sites to myosin (b) influx of calcium into the sarcoplasm (c) power stroke of the myosin heads (d) decrease in sarcoplasmic calcium level
20. At which length does a muscle generate the smallest total (=active + passive) force?
(a) markedly shortened (b) resting length (c) markedly lengthened
21. A gene may be affected by various types of mutation that can result in a genetic disorder.
Can a frame shift mutation have an activating effect?
(a) yes (b) no
22. Can duplication of an entire gene cause the same disorder as a nonsense mutation in that gene?
(a) yes (b) no
23. Can you exclude an robertsian translocation by exome sequencing?
(a) yes (b) no
24. A splice site mutation will change the length of a coded protein.
(a) correct (b) incorrect
25. What is an anticodon?
(a) three nucleotides that are complementary to nucleotides in mRNA that codes for an amino acid (b) three nucleotides coding for several amino acids
(c) three nucleotides that cannot bind to mRNA (d) three nucleotides that cannot bind to amino acids
26. Which type of mutation has a direct effect on protein translation and production?
(a) exon deletion or duplication (b) premature stop codon mutation (c) gene promotor mutation
27. A phenylketonuria patient appears to benefit strongly from being given tetrahydrobiopterin (BH4).
Which of the following mutations is consistent with this finding?
(a) a missense mutation in exon 1 (b) a nonsense mutation in exon 1
(c) a splice site mutation between exons 1 and 2 (d) a frame shift mutation in exon 1
28. What will happen to the phenylalanine level of a PKU (phenylketonuria) patient when he runs a marathon? His phenylalanine level will:
(a) increase (b) decrease (c) remain the same
29. Which process is affected by micro-RNAs?
(a) transcription (b) splicing (c) translation
(d) post-translational modification
30. What is the normal order of occurrence of hypoglycaemia symptoms?
(a) signs and symptoms of neuroglycopaenia appear first
(b) symptoms of neuroglycopaenia and adrenergic symptoms appear simultaneously (c) adrenergic symptoms appear first
31. What is the most serious type of glycogen storage disease?
(a) glucose-6-phosphatase deficiency
(b) glycogen debranching enzyme deficiency (c) liver glycogen phosphorylase deficiency
32. Absence of hepatomegaly (enlarged liver) rules out a diagnosis of hepatic glycogen storage disease.
(a) correct (b) incorrect
33. The palpitations (tachycardia, i.e., excessively rapid heart rate) affecting hypoglycaemia patients are caused by:
(a) neuroglycopaenia (b) the adrenergic response
34. A skeletal muscle fibre comprises sarcomeres consisting of tightly organized myofibrils, which are visible as a banding pattern of A and I bands. A young man lifts a heavy box. In the process, his biceps contracts and the sarcomeres become shorter.
What happens to the length of the A-band during the lifting (biceps contraction)? It:
(a) will become shorter (b) will become longer
(c) will remain at the same length
35.
The image above is a micrograph of developing foetal muscle tissue (Masson’s trichrome stain).
Which of the following tissues is the most likely source of the specimen shown? Tissue originating in the:
(a) arm
(b) large intestine (c) heart
(d) bladder
36. The cytoplasm in the neuronal perikaryon contains a basophil chromatophilic substance (Nissl substance).
Patches with a lot of Nissl substance in perikaryons are characterized by:
(a) accumulation of lipofuscin (an aging pigment) (b) concentration of mitochondria
(c) strongly developed rough endoplasmic reticulum (d) induction of many action potentials
37. Aerobic oxidation of one glucose molecule produces more energy than complete oxidation of one long-chain fatty acid molecule.
(a) correct (b) incorrect
38. During beta-oxidation, a fatty acid-coA molecule reacts with:
(a) water (b) oxygen
Open book
1. Which of the following pedigree charts is consistent with the description below?
Mr De Vries (indicated by the arrow) has a son with cystic fibrosis (CF), an autosomal recessive genetic disorder. Mr De Vries and his wife are both carriers of a mutation in the CFTR gene.
The fathers of Mr and Mrs De Vries are brothers.
Mr and Mrs De Vries each have one sister. Mrs De Vries’s sister is pregnant with her first child. All family members are in good health.
(a) pedigree chart A (b) pedigree chart B (c) pedigree chart C
2. The image below is the pedigree chart of a family suffering from a genetic disorder. The mode of inheritance is most consistent with autosomal dominant inheritance. However, in a specific situation this inheritance could be autosomal recessive.
Which situation?
(a) high penetrance (b) X inactivation
(c) high carriership frequency
3. What is the name of the inheritance pattern shown in item 2?
(a) quasi-dominant (b) autosomal dominant (c) X-linked recessive
4. What happens to a polymerase chain reaction (PCR) if there are no dNTPs in the reaction?
(a) it will be normal
(b) it will be an arbitrarily primed PCR (c) it will stop after a few rounds (d) it will not start
5.
Which of the following statements about the figure above is correct?
(a) this is a sagittal cross section, and the part in the yellow circle is the caudal end of the embryo (b) this is a sagittal cross section, and the part in the yellow circle is the cranial end of the embryo (c) this is a transverse cross section, and the part in the yellow circle is the left part of the embryo (d) this is a transverse cross section, and the part in the yellow circle is the right part of the embryo
6. The septum transversum is a primordium of the diaphragm.
Where in the embryo does the development of the septum transversum start?
(a) at the caudal end (b) at the rostral end (c) at the dorsal side (d) at the lateral side
7.
The arrow in the above image indicates a lining of the lungs.
Which germ layer is the origin of this layer?
(a) endoderm
(b) paraxial mesoderm (c) lateral mesoderm (d) intermediate mesoderm
8. When an action potential is conducted across an axon, the amplitude of the action potential decreases.
To which axons does the above statement apply?
(a) only to myelinated axons (b) only to unmyelinated axons
(c) to neither myelinated nor unmyelinated axons (d) to both myelinated and unmyelinated axons
9. A skeletal muscle fibre produces a certain force after a muscle fibre action potential has been generated by means of an end-plate potential.
What happens to the strength of a muscle fibre when the amplitude of the end-plate potential increases? Muscle strength will:
(a) remain the same (b) decrease (c) increase
10. The result of a heel prick test performed on a four-day-old girl shows that she has PKU. DNA diagnostics are used to detect the mutations responsible for her condition. (items 10-14) Which diagnostic test will be requested to detect these mutations?
(a) karyotyping (b) array CGH
11. A heterozygous mutation is detected in a cryptic splice site.
What effect does this mutation have on mRNA and at the protein level?
(a) mRNA cannot be translated and no protein is formed
(b) mRNA assumes a different length, thus protein length also changes (c) no mRNA is formed, which means no protein is formed either
12. Case: next three questions
On the other allele, two other heterozygous mutations are found. At protein level, one of these leads to conversion of a glutamine into a proline.
What do you call such a mutation?
(a) missense mutation (b) nonsense mutation (c) silent mutation (d) inversion
13. The other mutation (see previous item) is shown below at DNA level.
Normal mRNA sequence and associated amino acid sequence:
5’- AUG AAG UUU GGC UAA – 3’
Met Lys Phe Gly Stop DNA sequence found in the girl:
5’- AUG AAG UUU GGU UAA – 3’
What do you call such a mutation?
(a) missense mutation (b) nonsense mutation (c) silent mutation (d) inversion
14. Hypoglycaemia without ketonuria may be caused by hyperinsulinism as well as impaired fatty acid oxidation.
The distinction between the two patient groups can be made on the basis of the period between the last meal and the onset of hypoglycaemia.
(a) correct (b) incorrect
15. There is a list of substances that should be analysed in a child with unexplained hypoglycaemia before treatment can be initiated.
Which of the following substances is not on this list?
(a) Cortisol (b) Pyruvate
(c) β-hydroxybutyric acid
