Gene therapy

Question 1

What is somatic gene therapy

Answer 1

Somatic cell gene therapy is a technology where a functioning allele of a gene is introduced into a differentiated body cell that has faulty alleles, so that functioning polypeptides are made by the cells. The treated cells retain the faulty alleles so any offspring of a person treated with somatic cell gene therapy will still inherit the faulty gene

Question 2

What is germline cell therapy?

Answer 2

Germline cell gene therapy involves engineering a gene in a sperm cell, an ovum, or a zygote so that every cell in the growing individual has a non-faulty copy of the gene. The new gene may be inherited by any offspring.

Question 3

Is gene therapy effective?

Answer 3

Most gene therapies have yet to be very effective, for example, the effect may be short lived. In addition, gene therapy can only be used to treat genetic disorders caused by recessive alleles of a single gene (e.g., cystic fibrosis).

Question 4

What is gene therapy?

Answer 4

Gene therapy involves using various mechanisms to alter a person’s genetic material to treat, or cure, diseases

Question 5

Why is gene therapy used?

Answer 5

allows the possibilities of gene therapy being able to replace a faulty gene, inactivate a faulty gene or insert a new gene are growing

Question 6

Vectors are currently used as the delivery system, How are they used?

Answer 6

Viruses (eg. retroviruses and lentiviruses) are the most commonly used vectors as they have the mechanisms needed to recognise cells and deliver the genetic material into them

Question 7

What is somatic in simplest terms?

Answer 7

• does not target specific gametes or cells

Question 8

What are two types of somatic gene therapy?

Answer 8

• Ex-vivo
• In-vivo

Question 9

What is Ex-vivo?

Answer 9

Ex vivo – the new gene is inserted via a virus vector into the cell outside the body. Blood or bone marrow cells are extracted and exposed to the virus which inserts the gene into these cells. These cells are then grown in the laboratory and returned to the person by an injection into a vein

Question 10

What is in-vivo?

Answer 10

In vivo – the new gene is inserted via a vector into cells inside the body

Question 11

What are germ cells?

Answer 11

cells involved in sexual reproduction eg. gametes or an early embryo

Question 12

Why is it illegal for genetic material to be inserted into germ cells?

Answer 12

as any changes made to the genetic material of these cells is potentially permanent and could therefore be inherited by future generations