Genetic engineering (CCEA)

Genetic engineering changes the genome of an organism to introduce desirable traits eg increase yields, disease-resistant, and improve nutrients in food.

It is widely used in medicine, agriculture, and scientific research.

It can be carried out on plants and animals.

Some extra examples are below:

Genetic engineering is used to make human hormone insulin for the treatment of diabetes. The genome of bacteria are changed to include the human gene for insulin.

1. The human insulin gene is removed using a restriction enzyme.

2. A bacterial plasmid is cut open using the same restriction enzyme.

3. Restriction enzymes cut DNA creating complementary ‘sticky ends’ that join by base pairing.

4. A different enzyme is used to join the insulin gene and the bacterial plasmid.

5. The bacterial plasmid containing the insulin gene is placed into a bacterial cell. This is now a genetically modified bacterium.

6. The bacterial cells are grown in a fermenter where they rapidly reproduce under optimal conditions of warmth, moisture, and oxygen, producing large quantities of insulin.

7. Downstreaming occurs – the insulin is extracted, purified and packaged to ensure it is safe and effective for treating diabetes.

Advantages of genetically engineered insulin:

• No side effects or allergies

• No animals are killed or no ethical issues concerning the use of animals

• Large quantities can be made quickly and cheaply

• No rejection as it’s human insulin