WHAT IS ... GENE THERAPY?LO: Be able to describe what gene

therapy is and how it could be used.

STARTER: WHAT ARE THE LABELS??

B

A

C

E

D

GENES Specific sequence of bases that encode

instructions on how to make proteins. Genes are passed on from parent to

child. When genes are altered, and they don’t

produce the right proteins or correctly, a child may have genetic disorder.

What genetic disorders have you heard of?

GENE THERAPY An experimental technique used to treat

/ or prevent diseases.- by correcting faulty genes.

This is so that, in the future a gene can

be inserted into a patient’s cell instead of using surgery or drugs.

APPROACHES TO GENE THERAPY Replacing a mutated gene that causes

disease with a healthy copy of the gene. (most common)

HOW DOES IT WORK? A ‘normal’ gene is inserted into the

genome to replace and ‘abnormal’ disease-causing gene.

A vector (carrier molecule) is used to deliver the ‘normal’ gene to the patient’s target cell.

- normally a virus is the most common vector which has been genetically altered so that it can carry normal human DNA.

Virus vector

Vectors are used to deliver ‘normal genes’ to target cells

The target cells like the patient’s liver or lung cells are infected with the viral vector.

The vector then unloads its genetic material containing the gene into target cell.

Functional proteins are produced from the

‘normal’ gene and restores the target cell to normal state.

A PROMISING TREATMENT, HOWEVER ... The technique is risky and is still under

study to make sure it is safe and effective.

Only being tested for treatment of diseases that have no cure

LIMITATIONS AND RISKS This approach is limited in its application

as its used only with certain tissues and requires large amounts of DNA.

Patients have to undergo multiple rounds of gene therapy.

May trigger immune response Problems with viral response

ETHICAL CONSIDERATIONS - GENE THERAPY Are disabilities diseases? Should they be

cured or prevented? Do searching for the cure demean the

lives of those who are presently affected by disabilities.

It is very expensive – so who’ll have access to these? And who’ll pay?