JD - Genetic Therapeutics Flashcards
1
Q
What 4 types of diseases can gene therapy treat?
A
- Inherited diseases e.g. cystic fibrosis
- Cancers
- Infectious diseases
- Immune disorders
2
Q
What are the main 2 categories of gene therapy?
A
1) Germ-line cells
- Produce a permanent modification by modifying the DNA of a gamete or embryo
- Banned in humans for ethical reasons
2) Somatic cells
- Genetically modified by altering the composition of adult cells
- Only confined to that patient- not passed on
3
Q
What is involved in the first strategy of somatic cells? (3)
A
Modifying the disease cells
- Gene augmentation- Functional copies of the gene are added back into the cells that lack it
-
Gene silencing- The expression of a gene is selectively inhibited
-Achieved by turning off the transcription of the harmful gene - Repair of the mutant gene- Involves repairing the gene mutation
4
Q
What is involved in the second strategy of somatic cells? (2)
A
Selectively killing diseased cells
- Directly kill the disease-causing cells with a ‘suicide gene
- Indirectly killing the cells by enhancing the action of the immune system
5
Q
What is gene transfer?
A
The delivery of genetic material to the patient
6
Q
What are 2 approaches of gene transfer?
A
- In-vivo (direct delivery)
- Ex-vivo (cell-based delivery)
7
Q
How do liposomes help with gene transfer? (2)
A
Contain the therapeutic gene
- They are taken up into the cell via endocytosis or clathrin-coated pits
- The gene must be placed into a plasmid expression vector
8
Q
Why is the plasmid inefficiently transported to the nucleus?
A
Its size
9
Q
What are 2 methods of transporting the plasmid DNA into the nucleus?
A
- Conjugating specific DNA or protein sequences that are known to facilitate nuclear transport
- Compacting the DNA- So it is smaller in size and can move through the nuclear pores
10
Q
How does gene therapy help with Cystic Fibrosis?
A
A regular copy of the CFTR gene can be transported to the patient
