Gene Therapy and Gene Silencing Flashcards
1
Q
● Experimental technique that uses genes to treat or prevent disease
A
Gene therapy
2
Q
● Currently being tested only for diseases that have no other cures.
A
Gene therapy
3
Q
Enumerate the examples of diseases that have no other cures
A
Cancer, HIV, and other inherited diseases
4
Q
● Designed to introduce genetic material into cells to compensate for abnormal genes or to make a beneficial protein
A
Gene therapy
5
Q
In gene therapy, you insert a normal gene to _________ or _________ for an abnormal gene
A
replace or compensate
6
Q
DNA is transcribed to form mRNA which is translated to its product, protein (expressed product)
A
Centra dogma
7
Q
Enumerate the approaches in gene therapy
A
Replacing mutated gene
Inactivating, or “knocking out”
Introducing a new gene into the body
8
Q
The term used for the turn off the mutated gene
A
Inactivate
9
Q
The term used to diminish the production or expression of the mutated gene
A
Knocking out
10
Q
How does introducing a new gene into the body help?
A
Which will help fight against diseases
11
Q
In which year does the genetic engineering was first presented at the 6th international Congress of Genetics
A
1932
12
Q
In 1994, ________ and ________ suggested “genes could be transferred within nucleic acids”
A
MacLeod and McCarly
13
Q
Concept of genetic correction arise
A
1944
14
Q
In 1947, _________ was first to use the term gene therapy
A
Clyde E. Keeler
15
Q
In which year: set the basis of molecular genetics and gene transfer
A
1960s and 1970s
16
Q
In which year: The first deliberate transfer of foreign genes into human recipients, was performed by ____________
A
1970
Stanfield Rogers
17
Q
Establishment of recombinant DNA technology
A
1973
18
Q
In which year: Martin Cline at UCLA headed another highly controversial human trial designed to treat __________
A
July 1980
β-thalassemia
19
Q
an inherited blood disorder in which the body doesn’t make normal hemoglobin.
A
β-thalassemia
20
Q
There is a problem with the amino acid sequence of the β-globin chain (deletion)
A
β-thalassemia
21
Q
In which year: Enzyme-producing-gene-corrected cells were further theorized as a viable approach for treating ________
A
1983
Lesch–Nyhan disease
22
Q
x-linked recessive disorder
A
Lesch-Nyhan disease
23
Q
T/F First serious approved gene therapy trials happened two decades later in the USA:
A
F; just another decade later
24
Q
Advanced melanoma were treated with tumor-infiltrating lymphocytes isolated from solid tumors
A
First trial
25
Employed enzyme-transduced T-cells for adenosine deaminase (ADA) severe combined immunodeficiency
Second trial
26
What are the two types of gene therapy?
Somatic Cell Gene Therapy
Germ line cell gene therapy
27
Therapeutic genes transferred into somatic cells
Somatic Cell Gene Therapy
28
Example: introduction of genes into bone marrow cells, blood cells, skin cells etc
Somatic Cell Gene Therapy
29
T/F: In Somatic Cell Gene Therapy, it will be inherited in later generations
F; it will NOT be inherited
30
Somatic Gene Cell Therapy can be _____ or _______
Ex vivo
In vivo
31
Therapeutic genes transferred into germ cells (eggs and sperm cells)
Germ line cell gene therapy
32
Example: genes are introduced to egg cell or sperm cell
Germ line cell gene therapy
33
T/F: In germ line cell gene therapy. it will be inherited to next generation
T
34
● It only affects the targeted cells in the patient
Somatic cell gene therapy
35
● It cannot be transferred/passed to future generations (hindi namamana)
Somatic cell gene therapy
36
T/F: somatic cell gene therapy are short lived/short life-span
T
37
In somatic gene therapy, the transporting of gene to the target cell/tissue is _____________
problematic
38
Somatic gene therapy is acceptable/appropriate gene therapy for:
→ Cystic fibrosis
→ Muscular dystrophy
→ Cancer
→ Certain infectious diseases
39
● Has a possibility of inheritance
Germ line cell gene therapy
40
in germ line cell gene therapy, it has a potential of offering a ________ therapeutic effect to all those who inherit the target gene
permanent
41
T/F: in germ line cell gene therapy, it has the possibility of eliminating some diseases from a particular family.
T
42
● Raises controversies
Germ line cell gene therapy
43
Why are there controversies regarding germ line cell gene therapy?
→ There are concerns about the technical aspects of the experimental approach
→ Some people view this therapy as unnatural
→ Some of religious devotees likened it to playing with God
44
● Means external
Ex vivo gene therapy
45
→ Cells with the mutated genes will be modified outside the body and transplant it again in the body
Ex vivo gene therapy
46
In Ex vivo gene therapy:
Example: cells from patient’s ___________ or _________ are removed wherein they are isolated and cultured in the laboratory.
bone marrow or blood
47
T/F: in Ex vivo gene therapy, after the removal of cells from the patient, cells are then exposed to the virus that carries the desired gene (normal gene)
T
48
● Innovative
Ex vivo gene therapy
49
○ Proteins with genome within
Viruses
50
Basic pathogenesis of viruses
Infects healthy cells by inserting genome inside the cell
51
○ Virus used in ex-vivo is modified=_______ (________)
attenuated (non-infectious)
52
● Means Interior
In vivo gene therapy
53
→ Genes are changed in the cell within the body
In vivo gene therapy
54
T/F: in in vivo gene therapy, abnormal genes are changed after the cell is extracted from the patient
F: changed while the cell is inside the body
55
● The transfer of your corrected/normal/healthy gene requires a ________
Vector
56
● Vehicle for gene delivery
Vector
57
Vector
● Can be manipulated _______ to modify their genomes in order to insert a gene of interest
in vitro
58
● 2 main class of vectors:
→ Viral vectors
→ Non-viral vectors
59
IDEAL VECTORS
Target
Integrate
Activate
Avoid
60
T/F: No universal vector exists
T
61
● Cell with original genes
Viral vectors
62
● Vector inserts a new gene into cell
Viral vectors
63
New gene in the cell along with original genes
Viral vectors
64
Types of Viral Vectors
Retrovirus
Adenovirus
Adeno-associated virus
Herpes simplex virus
65
○ Majority of gene therapy clinical trial uses _________________
retrovirus & adenovirus
66
What are the Adeno-associated virus
○ Lentivirus
○ Poxvirus
○ α-virus
67
These viruses differ on how well they can transfer/insert the gene into the target cell.
Types of Viral Vectors
68
● Involves the use of physical approach/carrier-free gene delivery (Naked DNA)
Non-Viral Vectors
69
Non-Viral Vectors
Chemical Methods (uses synthetic vector)
→ Oligonucleotides
→ Lipoplexes and polyplexes
70
Enumerate Non-viral methods
Naked DNA
Oligonucleotides
71
Simplest method
Naked DNA
72
Naked DNA
● _________ injection of a naked DNA plasmid
Intramuscular
73
T/F: Injection of naked DNA intramuscularly has shown a very low expression in comparison of other methods.
T
74
Naked DNA
Electroporation and the use of a “________”
gene gun
75
uses high-pressured gas to shoot DNA-coated gold particles within the target cell.
Gene gun
76
Inactivate the genes
Oligonucleotides
77
● Uses antisense specific
Oligonucleotides
78
Disrupt the transcription of the faulty gene = no production of mRNA
Antisense specific
79
Oligonucleotides
● Uses small molecules of RNA called ______ (_____________)
siRNA (small interfering RNA)
80
siRNA (small interfering RNA) is used to signal the cell to cleave specific unit sequences in the mRNA transcript of the faulty gene which will disrupt _______
Translation
81
Oligonucleotides
Uses (single stranded/double stranded) oligodeoxynucleotides as a decoy for the transcription factors
double stranded
81
Oligonucleotides
Uses (single stranded/double stranded) oligodeoxynucleotides as a decoy for the transcription factors
double stranded
82
Chemical methods in Non-viral Vectors
Lipoplexes and polyplexes
83
T/F: in lipoplexes and polyplexes, to improve the delivery of the new DNA within the cell, the DNA must be protected from damage and its entry into the cell must be facilitated.
T
84
● New molecule have been created that have the ability to protect the DNA from undesirable degradation during the transfection process
Lipoplexes and polyplexes
85
insertion of nucleic acid within eukaryotic cell
Transfection
86
● Example of lipoplex is plasmid DNA can be covered with lipids.
Micelles
Liposomes
87
When the organized structure is complexed with DNA it is called a ________
Lipoplex
88
● The most common use of lipoplex is the gene transfer within a cancer cell wherein the supplied gene within the lipoplex has activated __________
tumor suppressor gene
89
T/F: Tumor suppressor gene increases the activity of oncogenes
F; decreases
90
Cancer genes
Oncogenes
91
T/F: Recent studies show the lipoplex is useful in transfecting respiratory epithelial cells.
T
92
three types of lipids
Anionic (negatively charged)
Neutral
Cationic (positively charged)
93
Neutral
Anionic and neutral lipids were used for the construction of _______ for synthetic vectors.
Lipoplex
94
T/F: Neutral lipids has a high amounts of toxicity but are also compatible with other body fluids
F; little toxicity
95
○ They can adapt to become tissue specific
Neutral lipids
96
○ Complicated and time-consuming to produce
Neutral lipids
97
Naturally bind/form complex with negatively charged DNAs
Cationic (positively charged) lipids
98
T/F: Since cationic lipids are positively charged, they can interact well with the cell membrane.
T
99
■ The insertion of lipoplex is easier from within the cell through the process of ________
endocytosis
100
○ The cationic property or cationic lipids can protect DNA against _______
degregation
101
What is another form of lipids
Polyplexes
102
→ A complex of polymers with DNA
Polyplexes
103
Polyplexes
→ Most consist of (ionic/cationic) polymers and their production are regulated by ionic interaction
cationic
103
Polyplexes
→ Most consist of (ionic/cationic) polymers and their production are regulated by ionic interaction
cationic
104
→ One large difference between the method of action of lipoplexes and polyplexes is that polyplexes (can/cannot) release their DNA load into the cytoplasm
cannot
cytoplasm
105
Coat transfection with endosome lipid agent such as _______________ must occur.
inactivated adenovirus
106
● Is a technique that aims to reduce or eliminate the production of a protein from it corresponding gene
Gene silencing
107
Gene silencing is described as “_______" of a gene by a mechanism other than genetic modification
Switching off
108
● Occurs when RNA is unable to make a protein during translation
Gene silencing
109
T/F: Gene silencing is completely similar from gene knockout
F; completely different
110
the expression of the gene is reduced
Gene knockdown
111
gene is completely erased from the organism's genome
Gene knockout
112
ADVANTAGES OF GENE SILENCING
1. It is cost-effective
2. It can induce viral resistance
3. It is a powerful tool for analyzing unknown genes in a sequence genome
4. Useful approach in future gene therapy
113
HOW DOES GENE SILENCING WORK?
Accomplished by binding a specific strand of RNA to an existing _______ strand
mRNA
114
example of specific strand of RNA binded during gene silencing?
siRNA (it will inhibit translation)
115
TYPES OF GENE SILENCING
Transcriptional gene silencing
Post transcriptional gene silencing
116
Promoter silenced
Transcriptional gene silencing
117
Transcriptional gene silencing
Genes hypermethylated in ___________ region
promoter
118
Purpose of transcriptional gene therapy
Viral immunity
119
Promoter active
Post transcriptional gene silencing
120
Post transcriptional gene silencing
Genes hypermethylated in _________ region
Coding
121
Purpose of post transcriptional gene silencing
Viral immunity
122
● A result of histone modification
Transcriptional gene silencing
123
→ When histones are modified, it will make it inaccessible to transcriptional machinery such as:
○ RNA polymerase
○ Transcription factors
124
● Formation of mRNA
Post transcriptional gene silencing
125
T/F: The formation of mRNA suppress the expression of mRNA (translation)
T
126
● Deepen the pigmentation in petunia
1990 Jorgensen
127
Introduction of transgenes homologous to endogenous
1990 Jorgensen
128
the introduction of transgenes homologous to endogenous in 1990 jorgensen often resulted in plants with both genes suppressed called ______
co-suppresion
129
Degradation of the endogenous and transgene.
1990 Jorgenses
130
Injection of either antisense or sense RNAs in the germline of ________
1995 Guo and Kemphues
Candida elegans
131
The 1998 Craig Mello and Andrew Fire is an extended experiment of _______, ____, and _______
Jorgensen, Guo, and Kemphues.
132
● Combination of sense and antisense
1998 Craig Mello and Andrew Fire
133
● RNA(=dsRNA).
1998 Craig Mello and Andrew Fire
134
T/F: Double-stranded RNA is 2x more effective than single stranded RNA
F; 10x
