Module 6: Gene therapy

Question 1

What is the purpose of gene therapy?

Answer 1

to replace faulty genes with healthy ones to prevent or treat genetic disorders

Question 2

Make 4 points about how gene therapy can treat genetic disorders

Answer 2

1.identify abnormal gene responsible for the disorder
2.engineeer a normal functioning version of this gene by removing it from healthy cells and synthesising it in a lab
3.deliver the normal gene to nuclei of target cells using a vector
4.ensure the gene is successfully integrated into the cells DNA and is expressed correctly

Question 3

How can gene therapy be used to counteract recessive disorders?

Answer 3

by adding functional dominant alleles that mask the expression of the recessive allele

Question 4

How can gene therapy be used to counteract dominant disorders?

Answer 4

by inserting DNA sequences that inactivate the harmful dominant alleles

Question 5

What are the 2 main types of gene therapy?

Answer 5

somatic gene therapy
germline gene therapy

Question 6

What is the difference between somatic and germline gene therapy?

Answer 6

somatic gene therapy replaces mutant alleles with healthy ones in body cells to treat diseases

germline gene therapy involves inserting healthy alleles into embryos to prevent disease from birth

Question 7

Describe how the tissues and organs affected are different between somatic and germline gene therapy

Answer 7

only specific tissues/organs are affected by somatic gene therapy , whereas germline gene therapy affects all cells within the body

Question 8

Give 4 ethical benefits of gene therapy

Answer 8

-extends lives by treating diseases/disorders
-enhances quality of life
-reduces overall disease burden on population
-germline gene therapy allows carrier parents to have children free of genetic disorders

Question 9

Give 4 disadvantges/challenges with somatic gene therapy

Answer 9

-body cells typically have short lifespan so eventually cells will be replaced with ones carrying faulty gene
-inserting healthy allele into nucleus can be challenging and delivering the allele to the cell can also be challenging
-maintaining expression of healthy allele can be challenging

Question 9

Give 4 general ethical issues/risks of gene therapy

Answer 9

-can be costly which reduces access
-diverts scarce healthcare resources
-there is a risk of causing unintended harm
-potential misuse for enhancing aesthetic attributes rather than treating medical needs

Question 10

Give 3 issues with germline gene therapy

Answer 10

-unborn child can’t give consent so their rights are violated
-it causes irreversible changes in which the long term outcomes aren’t fully understood
-could be used for selecting desirable traits rather than for medical reasons