Gene Therapy

Question 1

1. Gene therapy has the greatest potential with what 2 types of diseases?
2. What is it?

Answer 1

1. Genetic and cancer

2. Transfer of specific genetic material (usually DNA) into an affected patient

Question 2

Somatic vs germline gene therapy

Answer 2

Germline is introduced into all cells of the body-so genetic modification can be based on
Somatic has no affect on the germline (just somatic cells)

Question 3

Successful gene therapy requires what 2 ingredients

Answer 3

Therapeutic genes and efficient gene delivery system

Question 4

1. What is the gene delivery system in humans - be specific
2. Why?
3. Do they retain the genes involved in allowing genetic material to enter the cell and be expressed?

Answer 4

1. Vector - usually of viral origin
2. Natural part of a virus life cycle is for genetic material to enter a cell (pathogenesis of virus is removed tho)
3. Yes

Question 5

Name 4 types of vectors

Why is nonviral not really used?

Answer 5

Retrovirus, adenovirus, adeno-associated virus, nonviral virus

They require an alternative method of being introduced into a cell

Question 6

1. What is gene augmentation therapy? Used to treat what kind of diseases?
2. What is targeted killing of specific cells? Used to treat?

Answer 6

1. An extra copy of a normal gene is added to a cell - autosomal recessive
2. Transgene is toxic to the targeted cell - cancer

Question 7

Targeted inhibition of gene expression

1. What is it
2. Mechanism may involved blocking what 3 things?
3. Used against what type of dieases
4. Example of specific disease

Answer 7

1. Transgene interferes with expression of the disease gene at level of DNA, RNA or protein
2. Transcription, translation, or causing a specific RNA/protein to be degraded
3. Cancer and some autosomal dominant
4. Huntington

Question 8

Targeted gene mutation correction

1. Target may be?
2. What does it do to it
3. In RNA, what does it do
4. What is significant about this type of gene therapy

Answer 8

1. DNA
2. Homologous recombination of the mutated gene sequence
3. Correction of a splicing defect
4. Only type that might be acceptable at the germline level in humans

Question 9

Severe combined immunodeficiency disease (SCID):

1. Deficiency of what enzyme?
2. What type of disease
3. This enzyme is important in?
4. What 2 things will be inhibited
5. Results in lack of what 2 things?
6. Treatment

Answer 9

1. Adenosine deaminase
2. Autosomal recessive
3. Lymphocytes
4. Nucleotide metabolism and hence DNA replication/cell division
5. Lack of T and B lymphocytes
6. Usually die by age 2; must be kept in sterile bubble

Question 10

SCID:

1. Clone a normal adenosine deaminase gene and insert into __ vector
2. What does the vector do?
3. This was the first example of
4. Consequences of this gene therapy?

Answer 10

1. Retrovirus
2. Reverse transcribes RNA to DNA to regain normal immune function in lymphocytes
3. Successful gene therapy
4. Some patients got leukemia

Question 11

Transgenic animals express

Answer 11

Foreign genes

Question 12

Cloning mammals:

1. What first has to be done to egg cell
2. Then what?
3. The result would be a clone of what?

Answer 12

1. Nucleus must be removed
2. Nucleus of animal you want to clone has to be injected into donor egg cell
3. Of the cell that the nucleus was removed from

Question 13

Gene therapy is either delivering genes to ___

Why?

Answer 13

Cells of interest of tissues of interest

To repair something that is wrong (replace a gene, add a gene, etc.)