CGE: Using Recombinant DNA Technology

Question 1

Genetic engineering

Answer 1

When microorganisms, plants and animals are transformed using recombinant DNA technology.

Question 2

Transformed organisms

Answer 2

Also known as genetically engineered or genetically modified organisms.

Question 3

Transformed microorganisms can be made using what type of technology?

Answer 3

The same as in vivo cloning.

Question 4

When microorganisms, plants and animals are transformed using recombinant DNA technology.

Answer 4

Genetic engineering

Question 5

Also known as genetically engineered or genetically modified organisms.

Answer 5

Transformed organisms

Question 6

Describe how a transformed organism might be made to produce a useful protein:

Answer 6

1. DNA fragment containing protein gene, eg insulin gene, is isolated.
2. Fragment is inserted into plasmid vector.
3. Plasmid containing recombinant DNA is transferred into bacterium.
4. Transformed bacterium are identified and grown.
5. Insulin produced from cloned gene is extracted and purified.

Question 7

Describe how a transformed plant may be produced:

Answer 7

1. Gene that codes for a desirable protein is inserted into plasmid.
2. Plasmid added to bacterium which is used as a vector to get gene into plant cells.
3. If right promoter region is added, transformed cells will be able to produce desired proteins.

Question 8

Describe how a transformed animal might be produced:

Answer 8

1. Gene coding for a desirable protein is inserted into early embryo or into egg cells of a female.
2. If inserted early into an embryo = all body cells of resulting transformed animal will contain the gene.
3. If inserted into egg cells = all cells of offspring will contain the gene.

Question 9

How can scientists control what body cells in an animal the protein is produced in?

Why is this beneficial?

Answer 9

By using promoter regions that are only activated in specific cell types.

Makes harvesting protein easier and helps prevent damage to an organism.

Question 10

List three uses of recombinant DNA technology for humans:

Answer 10

1. Agriculture
2. Industry
3. Medicine

Question 11

What are the benefits of recombinant DNA technology for agriculture?

Answer 11

Transformed crops:

• Can have higher yields and more nutrients = can combat famine and malnutrition.
• Can have pest resistance = reduced use of pesticides = reduces costs and environmental problems.

Question 12

Give an example of a transformed crop:

Answer 12

Golden rice

• Contains one gene from a maize plant and one from a soil bacterium - enables rice to produce beta-carotene.
• Used by our bodies to make vitamin A.
• Golden rice is used to reduce vitamin A deficiencies in areas where thousands of children go blind as a result of it.

Question 13

What are the benefits of recombinant DNA technology in industry?

Answer 13

• Biological catalysts can be produced by transformed organisms - produced in large quantities for lower costs.

Question 14

Give an example of a transformed organism being used in industry:

Answer 14

• Chymosin - enzyme used in cheese-making.
• Can now be made using transformed organisms.
• So can be made in large amounts, relatively cheaply and without killing cows.

Question 15

What are the benefits of recombinant DNA technology in medicine?

Answer 15

• Drugs and vaccines can be produced by transformed organisms.
• Made quickly, cheaply and in large quantities.

Question 16

Give an example of recombinant DNA technology being used in medicine:

Answer 16

• Insulin to treat Type 1 diabetes used to come from animals.
• This didn’t work as well as it wasn’t human insulin.
• Human insulin can now be made from transformed microorganisms, using a cloned human insulin gene.

Question 17

What are the issues with the use of recombinant DNA technology in agriculture?

Answer 17

• Monoculture - whole crop is vulnerable to the same disease as plants are genetically identical and also reduces biodiversity.
• Superweeds - transformed crops interbreeding with wild plants result in uncontrollable spread of recombinant DNA with unknown consequences. Could lead to weeds resistant to herbicides.
• Organic farmers loss of income - crops contaminated by wind-blown seeds of nearby genetically modified crops.

Question 18

What are the issues with the use of recombinant DNA technology in industry?

Answer 18

• People may not have a choice about whether to consume GM food if not properly labelled.
• Economic loss - consumer markets, eg. EU, won’t import GM foods and products, so people who traditionally sold there may lose out.
• Globalisation driving out small businesses - small amount of biotechnology companies control forms of genetic engineering and get more powerful as tech develops.

Question 19

What are the issues with using recombinant DNA technology in medicine?

Answer 19

• Companies who own genetic engineering technologies may limit use of life-saving technologies for profit.
• Worry about technologies being used unethically - eg. designer babies.

Question 20

Apart from industry, agriculture and medicine, how else does recombinant DNA create issues?

Answer 20

Creates ownership issues.

Question 21

Give two examples of how recombinant DNA technology creates ownership issues:

Answer 21

• Who owns genetic material after extraction - donor or researcher? Should the individual own the right to their own genetic info or should the researcher be able to use it for medicine development or diagnosis?
• Large corporations own patents to particular seeds - can charge high prices, including a ‘technology fee’, and can require farmers to repurchase seeds each year. Farmers can also be sued if non-GM crops are contaminated by GM crops.

Question 22

What are the humanitarian benefits to recombinant DNA technology?

Answer 22

• Agricultural crops that reduce famine and malnutrition risk, eg. drought resistant crops.
• Transformed crops can produce pharmaceutical products which could make drugs more easily available, eg. in places where refrigeration isn’t available.
• Medicines could be produced more cheaply - increased affordability.
• Can be used in gene therapy to treat diseases.

Question 23

Describe how gene therapy works:

Answer 23

• Identify whether disorder is caused by mutated dominant allele or two mutated recessive alleles.
• Mutated dominant allele = ‘silence’ dominant allele by inserting DNA in middle so it doesn’t work.
• Mutated recessive alleles = add a working dominant allele to supplement the faulty ones.

Question 24

Gene therapy

Answer 24

A form of recombinant DNA technology that involves altering the defective genes inside cells to treat genetic disorders and cancer.

Question 25

A form of recombinant DNA technology that involves altering the defective genes inside cells to treat genetic disorders and cancer.

Answer 25

Gene therapy

Question 26

The processes in gene therapy involve inserting a DNA fragment into the person’s original DNA.

How is this done?

Answer 26

• Allele inserted into cells using vectors like in recombinant DNA technology.
• Different vectors can be used: altered viruses, plasmids or liposomes (spheres made of lipid).

Question 27

What are the two types of gene therapy?

Answer 27

Somatic therapy

Germ line therapy

Question 28

Describe somatic gene therapy and give an example:

Answer 28

• Altering the alleles in body cells, particularly cells most affected by the disorder.
• EG. somatic therapy for CF targets epithelial cells lining lungs - but offspring could still inherit disease as sex cells not affected.

Question 29

Describe germ line gene therapy:

Answer 29

• Involves altering the alleles in the sex cells.
• Every cell of offspring produced from cells will be affected by gene therapy and won’t suffer from the disease.
• Currently illegal.

Question 30

What are some ethical issues with gene therapy?

Answer 30

• Worries technology might be used for non-medical purposes, eg. treating cosmetic effects of ageing.
• Potential to do more harm than good, eg. overexpression of genes.