Exam 5 Flashcards
(95 cards)
1
Q
50% chance of passing the trait to each child (male or female). Unaffected relatives or siblings do not transmit the disorder, and age of onset is delayed.
A
Autosomal dominant trait
2
Q
All children of an affect parents are carriers, with early age onset. Unaffected siblings may be carriers with 25% chance of an affected child and noncarrier child and 50% carrier child.
A
Autosomal recessive trait
3
Q
Likelihood that a clinical condition will occur when a particular genotype is present (complete or incomplete)
A
penetrance
4
Q
What are the two genetic variants using substitutions?
A
Missense- incorrect amino acid
Nonsense- replace amino acid with stop codon
5
Q
What are the two genetic variants using frameshift?
A
insertions and deletions
6
Q
What type of trait disorder is FH?
A
autosomal dominant LOF
7
Q
What type of trait disorder is osteogenesis imperfecta?
A
autosomal dominant LOF
8
Q
What type of trait disorder is PCSK9’s affect on LDL-R?
A
autosomal dominant GOF
9
Q
What type of trait disorder is cystic fibrosis?
A
autosomal recessive LOF
10
Q
50% chance of passing the gene to their sons and daughters, however only males are affected
A
X-linked recessive
11
Q
A. Autosomal dominant
B. Autosomal recessive
C. X-linked Recessive
D. Mitochondrial
A
A.
12
Q
A. Autosomal dominant
B. Autosomal recessive
C. X-linked Recessive
D. Mitochondrial
A
B.
13
Q
A. Autosomal dominant
B. Autosomal recessive
C. X-linked Recessive
D. Mitochondrial
A
C.
14
Q
A. Autosomal dominant
B. Autosomal recessive
C. X-linked Recessive
D. Mitochondrial
A
D.
15
Q
State whether the neurodegenerative triplet repeat mutation is dominant or recessive:
Huntington
Fragile X
Freidreich ataxia
A
Huntington- Dom
Fragile X- Dom
Freidreich ataxia- Recessive
16
Q
Mutation where females affected will transmit to 100% of children. Males do not pass down trait but can be affected.
A
Mitochondrial
17
Q
Disorder characterized by a change in autosome number and are more sever than single gene disorders
A
cytogenetic disorders
18
Q
In what parts of meiosis can chromosome nondisjunction occur?
A
Meiosis I and II
18
Q
In what parts of meiosis can chromosome nondisjunction occur?
A
Meiosis I and II
19
Q
Cytogenetic condition with an increase in chromosome number
A
down syndrome
20
Q
Cytogenetic condition with an decrease in chromosome number
A
Turner Syndrome
21
Q
What type of inheritance pattern is involved in genetic imprinting?
A
Complex inheritance patterns
22
Q
What type of inheritance pattern is involved in genomic imprinting?
A
Complex inheritance patterns
23
Q
Genetic condition where some regions of DNA are turned off (inactivated) in the copy received from the mother or the father
A
Genomic imprinting
24
When discussing human genetic studies, the preferred term to describe a permanent change in the sequence of a gene is:
A. Variant
B. Mutation
C. Modification
D. Polymorphism
A. Variant
25
Silent mutations:
a. Are the most common genetic cause of deafness in Caucasians
b. Are also known as balanced translocations since they do not result in loss genetic material or changes in the DNA sequence
c. Can change the amino acid sequence of a protein if they occur in the first position of a codon
d. Are most likely a benign change to the DNA sequence
d. Are most likely a benign change to the DNA sequence
26
Down Syndrome is most commonly caused by:
a. Ring chromosome 14
b. X chromosome monosomy
c. Y chromosome monosomy
d. Chromosome 21 trisomy
d. Chromosome 21 trisomy
27
True/False: Penetrance refers to the percentage of people who have a disease-causing mutation that show traits associated with this change
True
28
Which of the following is an example of variable expressivity?
a. One male child of a mother who carries the mutation for Hemophilia A has the trait, but a second male child does not
b. One male child of a father who has a mutation in the gene encoding the LDL receptor has familial hypercholesterolemia, but a second male child does not
c. A male child of a mother who carries the mutation for Hemophilia A has the trait, but a female child does not
d. One male child of a father who has a mutation in the gene encoding the collagen a1 subunit has hearing loss, but a second male child has normal hearing but suffered ten bone fractures
d. One male child of a father who has a mutation in the gene encoding the collagen a1 subunit has hearing loss, but a second male child has normal hearing but suffered ten bone fractures
29
Which of the following mainly affect males?
a) A dominant gain-of-function mutation in a gene located on chromosome 7
b) A dominant negative mutation in a gene located on chromosome 20
c) A recessive loss-of-function mutation in a gene located on chromosome 2
d) A recessive mutation on the X chromosome
e) A dominant loss-of-function mutation in a gene located on chromosome 7
d) A recessive mutation on the X chromosome
30
The mutation that likely leads to frameshift:
a) Changing C to G in the codon TGC, resulting in a change of the coded amino acid from cysteine to tryptophan
b) Changing C to T in the codon TGC, resulting in no change in the coded amino acid
c) Changing C to A in the codon TGC, resulting in a change of the coded amino acid from cysteine to stop
d) Inserting a C before the codon TGC, resulting in a change of the coded amino acid from cysteine to leucine
d) Inserting a C before the codon TGC, resulting in a change of the coded amino acid from cysteine to leucine
31
Huntington's disease is a genetically inherited neurodegenerative disease. Patients often have more than 40 CAG repeats in one of the exons in the huntingtin gene. Which of the following is the most likely outcome?
a) A decrease in the huntingtin gene transcription
b) An increase in the huntingtin gene translation
c) A change in the huntingtin protein structure and function
d) A change in the stability of the huntingtin mRNA
c) A change in the huntingtin protein structure and function
32
Cancer cells are (more/less) differentiated and (poorly/well) demarcated and differentiated.
Cancer cells are less differentiated and poorly demarcated and differentiated.
33
Estimate of aggressiveness or level of malignancy based on microscopic examination of tumor cell morphology; qualitative nature
Grading
34
Estimate of aggressiveness or level of malignancy based on size of the primary lesion, extent of spread, and presence or absence of metastases; quantitative nature
Staging
35
Genes that encode proteins that promote cancer
oncogenes
36
Genes that encode proteins that inhibit cancer
tumor suppressor genes
37
Type of childhood cancer that results from a single, recessive, inherited genetic mutation. It is the result of mutation or deletion of a single gene.
Retinoblastoma
38
Tumor suppressors are (dominant/recessive) and need (heterozygous/homozygous) deletion/mutation for both alleles.
Tumor suppressors are recessive and need homozygous deletion/mutation for both alleles.
39
Protein that results as a chromosomal translocation (oncogene). It produces a hyperactive kinase that drives proliferation in leukemia.
BCR-ABL
40
Which of the following statements about tumor suppressor genes is TRUE?
A) Tumor suppressor genes cause cancer.
B) The normal functioning of tumor suppressor genes prevents cancer.
C) Mutations in tumor suppressor genes never lead to cancer.
D) Duplications in tumor suppressor genes are common in cancer
B) The normal functioning of tumor suppressor genes prevents cancer.
41
Theory that LOF mutations in both alleles of these genes are typically required for tumor formation
Two-hit hypothesis
42
Repair of double stranded DNA breaks; inherited mutations lead to breast and ovarian cancer
A. BRCA 1/2
B. BLM
C. ATM
D. TP53
A. BRCA 1/2
43
Inherited mutations lead to many different cancers; Li-Fraumeni syndrome
A. MLH1
B. XP
C. TP53
D. PMS2
C. TP53
44
Syndrome caused by germ-line mutations (DNA mismatch repair genes)
A. MLH1
B. HNPCC
C. TP53
D. PMS2
B. HNPCC
45
Extreme sensitivity to UV; mutations involve NER (nucleotide excision repair)
A. ATM
B. TP53
C. BLM
D. XP
D. XP
46
Mutation in repairing double stranded DNA breaks; neurodegenerative disorder with increased lymphoma and leukemia incidence (ataxia telangiectasia)
A. ATM
B. TP53
C. BLM
D. XP
A. ATM
47
Mutation in DNA helicase involved in DNA replication/repair/recombo. Rash and high likelihood of many cancers; Bloom syndrome
A. ATM
B. TP53
C. BLM
D. XP
C. BLM
48
The critical time point when cells decide whether or not to enter the cell cycle
R point
49
The major role of G1/S checkpoint in cell cycle is to:
A) Check whether synthesis of DNA is complete
B) Check for sufficient nutrients and building blocks for replication
C) Check whether chromosomes are attached to spindles
D) All of the above
B) Check for sufficient nutrients and building blocks for replication
50
Which signaling leads to cell proliferation:
A. MAP kinase
B. JAK/STAT
C. P13K/AKT1
D. A and C
E. All of the above
E. All of the above
51
Which activate cancer? (O) Tumor suppressor? (TS)
RAS
P13K
AKT
PIP2
BRAF
TSC
ERK
mTOR
PTEN
PIP3
MEK
RAS (O)
P13K (O)
AKT (O)
PIP2 (TS)
BRAF (O)
TSC (TS)
ERK (O)
mTOR (TS)
PTEN (TS)
PIP3 (O)
MEK (O)
52
Tyrosine signaling pathway
See image
53
Match as growth inhibitor (GI), growth factor (GF), or CDK:
EGF
p16
p53
TGF-Beta
PDGF
EGF (GF)
p16 (CDK)
p53 (GI)
TGF-Beta (GI)
PDGF (GF)
54
What is the pathway between S and G1 that leads to transcriptional activation/block?
Note: GI stimulates CDK inactivating cyclins
GF activate cyclins that then turn hypo RB to hyper RB
55
What three genes if given a loss of function lead to disruption of apoptosis?
loss of: p53, p21, and BAX
56
Tumor cells produce ______ to promote angiogenesis
A. EGFR
B. VEGF
C. TGF
D. VHL
B. VEGF
57
Inherited ______ deletions increase incidence of kidney cancer
A. EGFR
B. VEGF
C. TGF
D. VHL
D. VHL
58
Nonsense mutation refers to:
A. A single base substitution that changes an amino acid to another amino acid in the same category in terms of charge, hydrophobicity and polarity.
B. A single base substitution that does not change the coded amino acid.
C. A single base substitution that causes termination of protein translation.
D. Insertion of a single nucleotide that causes a stop codon
E. Deletion of a single nucleotide that causes a stop codon
C. A single base substitution that causes termination of protein translation.
59
Which of the following mutations may lead to frameshift?
A. A single base substitution that changes an amino acid to another amino acid in the same category in terms of charge, hydrophobicity and polarity.
B. A single base substitution that changes an amino acid to another amino acid in a different category in terms of charge, hydrophobicity and polarity.
C. Insertion of two nucleotides
D. Trinucleotide repeat mutations
E. All of the above
C. Insertion of two nucleotides
60
The major cause of aneuploidy is:
A. Amplification of one or more chromosomes.
B. Defect in cell mitosis.
C. Fragmentation of chromosomes.
D. Nondisjunction of a homologous pair of chromosomes at the first or second meiotic division.
E. All of the above
D. Nondisjunction of a homologous pair of chromosomes at the first or second meiotic division.
61
Huntington disease is a genetically inherited neurodegenerative disease. Patients often have more than 40 CAG repeats in one of the exons in the huntingtin gene. These CAG repeats likely cause:
A. An increase in the huntingtin gene transcription.
B. An increase in the huntingtin gene translation.
C. Alteration of the Huntingtin protein structure and function.
D. An increase in the Huntingtin mRNA degradation.
E. An increase in the Huntingtin mRNA stability.
C. Alteration of the Huntingtin protein structure and function.
62
Patient with a gain-of-function mutation in one copy of the gene
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
A. Autosome dominant disorder
63
Patient with a three-fold more protein product caused by a mutation in one copy of the gene
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
A. Autosome dominant disorder
64
Both sons and daughters could be affected.
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
D. A and B
65
All children (100%) of an affected parent are carriers
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
B. Autosome recessive disorder
66
The altered gene product (protein) can antagonize the function of the wild-type proteins
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
A. Autosome dominant disorder
67
One of the patient’s parents must also be a patient
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
A. Autosome dominant disorder
68
Mutations that often affect structural proteins
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
A. Autosome dominant disorder
69
Mutations that often affect enzymes
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
B. Autosome recessive disorder
70
Daughters are rarely affected
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
C. X-linked recessive disorder
71
Female carriers have a 50% of chance of passing the gene to their sons and daughters
A. Autosome dominant disorder
B. Autosome recessive disorder
C. X-linked recessive disorder
D. A and B
E. B and C
C. X-linked recessive disorder
72
Jennifer was born normal 9 months ago, and her parents and three other siblings (two brothers and one sister) are healthy. However, she appears to have a slow development compared to normal growth of infants. Her parents contacted her pediatrician last week, and the blood examination revealed that Jennifer has an abnormally high level of plasma phenylalanine. The doctor asked the parents, and found that one of Jennifer’s uncles (father side) is suffering from phenylketonuria (high concentration of phenylalanine in urine), a disease that is caused by mutations in phenylalanine hydroxylase, an enzyme that catalyzes the rate-limiting step in the phenylalanine catabolism. Based on this information, it is likely that phenylketonuria is:
A. An autosomal dominant disorder.
B. An autosomal recessive disorder.
C. An X-linked recessive disorder
D. An X-linked dominant disorder
E. None of the above
B. An autosomal recessive disorder.
73
Genomic imprinting defects refer to:
A. Epigenetic inactivation of a maternal or paternal homologous gene.
B. Epigenetic inactivation of a pair of homologous genes.
C. Deletion of a pair of homologous genes.
D. B and C.
E. A, B and C.
A. Epigenetic inactivation of a maternal or paternal homologous gene.
74
Compared with benign tumors, which of the following is NOT the characteristic of malignant tumors?
A. Malignant tumors grow more rapidly.
B. Malignant tumors are more invasive.
C. Malignant tumors are poorly differentiated.
D. Malignant tumors tend to metastasize to distant organs.
E. Malignant tumors are bigger.
E. Malignant tumors are bigger.
75
In order to metastasize to distant organs, cancer cells must express:
A. Enzymes to break down the surrounding ECM and gain access to blood circulation.
B. Proteins that can kill immune cells.
C. p53 that can induce apoptosis of fibroblasts in ECM.
D. VEGF to form new blood vessels to deliver cancer cells to blood circulation.
E. Ligands that bind to kinase receptors.
A. Enzymes to break down the surrounding ECM and gain access to blood circulation.
76
Which of the following may NOT lead to cancer development?
A. Gain-of-function mutations in Ras.
B. Amplification of the EGFR gene.
C. Gain-of-function mutations in Raf.
D. Gain-of-function mutations in p53.
E. Overexpression of MEK.
D. Gain-of-function mutations in p53.
77
Herceptin is a monoclonal antibody that can recognize HER2, a member of the EGFR family receptors. Before treating breast cancer patients with Herceptin, doctors need to verify that:
A. HER2 gene is amplified or the its expression is higher
B. HER2 gene is lost
C. HER2 has loss-of-function mutation
D. The ligand for HER2 is present
E. None of the above
A. HER2 gene is amplified or the its expression is higher
78
The loss of p53 function could potentially lead to the following defects EXCEPT:
A. Inability to induce cell cycle arrest.
B. Inability to repair DNA damages.
C. Inability to induce apoptosis.
D. Inability to induce necrosis
D. Inability to induce necrosis
79
The “two-hit” hypothesis for tumor suppressors refers to:
A. That an oncogenic activation occurs first before the loss of a tumor suppressor.
B. That two suppressor genes must be inactivated for tumor development.
C. That two mutant alleles for a tumor suppressor must be inherited from father and mother.
D. That two alleles for a tumor suppressor must be inactivated in order to show effect.
E. That one mutant allele must be inherited and another allele must be inactivated in somatic cells.
D. That two alleles for a tumor suppressor must be inactivated in order to show effect.
80
Loss-of-function mutations in DNA repair genes often lead to cancer development. This is because:
A. DNA damages cannot be properly repaired and mutations are accumulated with cell divisions.
B. These DNA repair genes are also involved in apoptosis.
C. All DNA repair genes are also tumor suppressors.
D. DNA repair genes are on the same chromosomes with tumor suppressor genes.
E. All of the above.
A. DNA damages cannot be properly repaired and mutations are accumulated with cell divisions.
81
Targeted therapy is an important treatment strategy for cancer patients. Herceptin is an monoclonal antibody that can bind HER2 and is clinically used to treat breast cancer patients. Which of the following patients may benefit MOST from the use of Herceptin?
A. Patients with HER2 overexpression.
B. Patients with HER2 expression negative.
C. Triple negative patients.
D. Patients with HER1 overexpression
E. Triple positive patients
A. Patients with HER2 overexpression.
82
Susan is diagnosed with breast cancer, and she has amplification of the EGFR gene. She could benefit from the following treatments EXCEPT.
A. EGFR inhibitors.
B. Ras inhibitors.
C. ER targeted anti-hormone therapy.
D. Raf inhibitors.
E. MEK inhibitors.
C. ER targeted anti-hormone therapy.
83
Chronic viral infections could potentially lead to cancer development by the following mechanisms:
A. Some viral proteins may induce chronic inflammatory response.
B. Some viral DNA may integrate into human genome and activate proto-oncogenes.
C. Some viral proteins may suppress the function of tumor suppressors such as p53 and Rb.
D. Some viral proteins may disrupt normal cell cycle control.
E. All of the above.
E. All of the above.
84
Some virus such as HTLV-1, HPV and EBV can cause cancer development. Which of the following statements about the mechanisms by which these viruses cause cancer development is FALSE?
A. HTLV-1 TAX protein can induce chronic inflammatory response.
B. HTLV-1 TAX and HPV E6 can inactivate p53.
C. HPV E7 can dissociate Rb from E2F.
D. LMP proteins from EBV can activate mitogenic pathways.
E. Viral proteins are tumor suppressors.
E. Viral proteins are tumor suppressors.
85
Cancer cells have limitless replication potential. This is usually due to:
A. Oncogenic activation of the Ras proto-oncogene.
B. Deletion of the Rb alleles.
C. Overexpression of telomerase.
D. Amplification of c-Myc oncogene.
E. All of the above.
C. Overexpression of telomerase.
86
B cell infections are kept silent by functional ______
A. M cells
B E6 and E7
C. T cells
T cells
87
Expresses LMP1 and LMP2 that activate mitogenic signaling pathways (B cells)
A. MCPV
B. HTLV-1
C. EBV
D. KSHV
C. EBV
88
Express viral proteins including vFLIP that increases metastasis and angiogenesis
A. MCPV
B. HTLV-1
C. EBV
D. KSHV
D. KSHV
89
Causes Merkel cell carcinoma of skin; requires both infection and then mutations of the Large T antigen to form a truncated version
A. MCPV
B. HTLV-1
C. EBV
D. KSHV
A. MCPV
90
Causes cervical cancer with two viral proteins:
E6 targets ______, E7 targets _____
HPV:
E6 targets p53, E7 targets Rb
91
Produces TAX protein in host cell, increasing the expression of genes that promote proliferation, DNA repair, and resistance to apoptosis
A. MCPV
B. HTLV-1
C. EBV
D. KSHV
B. HTLV-1
92
What is the pathway for colon carcinogenesis?
Loss of APC, GOF mutation of RAS gene, LOF mutation of DCC, SMAD2 and SMAD4 tumor suppressors, Loss of p53
93
Used to estimate gene copy number or IHC to assess protein expression and tissue distribution
FISH
94
Chronic viral infections could potentially lead to cancer development by which of the following mechanisms?
A. Some viral proteins may induce chronic inflammatory response
B. Some viral DNA may integrate into human genome and activate proto-oncogenes
C. Some viral proteins may suppress the function of tumor suppressors such as p53 and Rb
D. Some viral proteins may disrupt normal cell cycle control
E. All of the above
E. All of the above
