Gene Therapy

Question 1

Germ line therapy involves…

Answer 1

1. Transfection of germ/omnipotent embryonic cell
2. Carrier of deleterious allele cured & some gametes
3. End of heritability of the disorder
4. Genetic changes can go beyond treated individual
5. Ethical debate

Question 2

Somatic gene therapy…

Answer 2

1. Targets only the affected body cells
2. Therapeutic thresholds differ between disorders
3. All affected individuals able to give consent

Question 3

In vivo gene therapy transfer vector delivered…

Answer 3

In a cell selective manner:
Either
1. Direct tissue injection
2. Receptor-mediated processes

Question 4

Ex vivo gene therapy involves…

Answer 4

1. Tissue removal
2. Transfection of cells in culture
3. Reimplantation of genetically altered cells

Question 5

Following ex vivo culture in conditions that stimulate cell proliferation…

Answer 5

Cells exposed to retroviral vector expressing functional cDNA copy of defective gene and then infused back into patient.

Question 6

In gene-corrected cells, full reconstitution of immune cell compartments is obtained even from…

Answer 6

A few engrafted progenitor cells (may occur without conditioning)

Question 7

Amount of gene therapies approved in EU & US

Answer 7

EU: 15 (7 cancer, 8 genetic disorders)
US: 16 (8 cancer, 8 genetic disorders)

Question 8

USA requires approval from local institutional biosafety committee/review board for experiments using…

Answer 8

Transfer of rDNA

Question 9

After approval of rDNA transfer experiments (by local institutional biosafety committee/review board)

Answer 9

Proposals then considered by rDNA Advisory Committee (RAC) & FDA

Question 10

Non-therapeutic use of genes/cells/genetic elements/modulation of expression to improve athletic performance

Answer 10

Defined as gene doping by the WADA

Question 11

Erythropoietin

Answer 11

1. Secreted by Kidneys (under hypoxic stress)
2. Normal EPO levels = 10mU/ml
   Hypoxic stress levels = 10,000mU/ml
3. EPO gene regulated by Hif1-alpha (TF)
4. Recombinant EPO used to treat anaemia (chronic kidney failure/chemotherapy)
5. Endogenous EPO is highly glycosylated (40% of total weight)

Question 12

Isoelectric focusing of rEPO & uEPO

Answer 12

rEPO is much more basic than uEPO

Question 13

MSTN

Answer 13

A myokine produced and released by myocytes (Inhibit muscle growth)

Question 14

MSTN mutations result in…

Answer 14

Increased muscle mass (target for muscular Dystrophies)

Question 15

Rate of homologous recombination can be increased by…

Answer 15

Introducing targeted DNA Ds break
(First done in mammalian cells with target sequence of meganuclease I-SceI)

Question 16

To boost HR at a gene region of interest…

Answer 16

Nuclease are required