Treatment for Genetic Diseases(5)

Question 1

What are three disease specific methods of treatment of metabolic disorders?

Answer 1

1- Dietary modification/ restriction

2- Inhibition

3- Depletion

Question 2

Give an example of using depletion to treat a metabolic disorder?

Answer 2

Hereditary hemochromatosis (accumulation of Fe in the blood) can be controlled by regular phlebotomy

Question 3

What is the theory behind extracellular protein replacement?

Answer 3

If a protein is missing, add it back in

Question 4

What are two examples of extracellular protein replacement?

Answer 4

Hemophelia A

alpha1- antitrypsin deficiency

Question 5

Problems with extracellular protein replacement?

Answer 5

Cost, availability, antibody production in patient, contamination

Question 6

What is an example of intracellular protein replacement therapy?

Answer 6

Gaucher disease

Question 7

Give an example of enhancing genetic expression to treat a genetic disease:

Answer 7

Sickle cell anemia treatment with Decitabine (which leads to hypomethylation of DNA and increased levels of HbF)

Question 8

What happens in a bone marrow transplant (as a method for treating hematologic disorders)?

Answer 8

Collect the marrow/ stem cells from the patient or from a matched donor.

Transplantated cell will reestablish in the new host and will hopefully be disease free

Question 9

Aside from hematologic disorders, what other genetic diseases can bone marrow transplantation help with?

Answer 9

Hysosomal storage diseases

Question 10

What are the two types of stem cells?

Answer 10

embryonic (pluripotent)

somatic (limited to tissue of origin)

Question 11

Embryonic stem cells have a potential therapeutic use for?

Answer 11

Parkinsons disease

Alzheimers disease

Question 12

Embryonic stem cells are potential sources of cells for?

Answer 12

Tissue grafting

Organ transplants

Question 13

What are the problems with allogenic stem cell use?

Answer 13

Immunosuppression

Graft vs Host disease

Question 14

What are iPS stem cells?

Answer 14

Induced pluripotent stem cells that have been “reprogrammed”

Beneficial be cause there is less chance of immune rejection.

Question 15

What is the process of cloning?

Answer 15

Cell obtained from donor

Unfertilized egg is obtained from another individual and enucleated

Nucleus from the donor cell is inserted into the enucleated oocyte.

Implanted into a surrogate mother.

Question 16

What are some ill effects of cloning?

Answer 16

Possible negative impacts on genes and chromosomes

Normal cellular aging is still a problem.

Personality, disposition, size are variable.

Question 17

Definition of gene therapy?

Answer 17

Deliberate introduction of genetic material into human somatic cells for a therapeutic, prophylactic or diagnostic purpose

Question 18

What are the three general classes of gene therapy?

Answer 18

1. Correct a loss of function mutation by incorporation of a functional gene
2. Compensate for a deletorious allele by replacement or inactivating the mutant allele
3. Adding genetic material that has pharacological effects

Question 19

What are the requirements for success of gene therapy?

Answer 19

1- Identification of gene

2- Availability of gene sequence or cloned DNA from the gene of interest

3. ID of target tissue
4. Ability to deliver to target tissue
5. Understanding of gene biochemistry
6. Understanding of expression

Question 20

Major limitation of gene therapy?

Answer 20

Delivery of gene to target….the vector must be able to carry DNA and insert the DNA into the target cell.

Question 21

What is in vivo gene therapy?

Answer 21

Genes are incorporated into vectors and targeted to specific cells in the body?

Question 22

What is ex vivo gene therapy?

Answer 22

Cells are extracted from the patient and genetically modified The altered cells are then returned to the patient.

Question 23

What was the first case of successful gene therapy?

Answer 23

ADA deficiency which results in SCID.

Question 24

What is antisense DNA therapy?

Answer 24

Decreased protein production because translation is blocked.

Usefull in therapy.

Question 25

What is RNAi?

Answer 25

Targeted degredation of mRNA.

Destroy mRNA from negative dominant mutation while leaving the second allele alone

Question 26

Why is the adeno-associated virus a good vector?

Answer 26

Non-pathogenic

Decreased likelihood of immune reaction