GE Crops - Background Info and Case Studies

Question 1

How are GE crops regulated compared to outcrossing and mutagenesis in many countries?

Answer 1

Outcrossing and mutagenesis are considered to be conventional breeding methods and are regulated differently than GE crops. GE crops are regulated a lot more stringently and are banned in some countries

Question 2

What is the source of genetic variation for GE crops?

Answer 2

Can be anything. Another plant species, the same plant species, bacteria, animal, protist, fungi

Question 3

Why would we want to use genetic engineering to introduce a gene from the same plant species?

Answer 3

Genetic engineering is much faster than outcrossing

Question 4

Where and when were the first GE crops planted in the environment?

Answer 4

In the US in 1996

Question 5

Which 5 countries grow the most GE crops?

Answer 5

US, Brazil, Argentina, Canada, India (in that order)

Question 6

Which GE crops are grown the most worldwide?

Answer 6

Soybeans, maize, cotton, canola, sugar beets, eggplant

Question 7

What GE crops are grown in Alberta and Canada?

Answer 7

Canola, sugar beets, maize, soybean

Question 8

Which 4 GE crops make up the vast majority of GE acreage worldwide?

Answer 8

Soybeans, maize, cotton, canola

Question 9

What are the 3 major traits that the vast majority of GE crops are engineered to have?

Answer 9

1. Herbicide resistance
2. Insect resistance
3. Disease resistance

Question 10

Why aren’t crops genetically engineered to improve yield?

Answer 10

Not determined by a single gene, so much harder to modify

Question 11

What 6 “next generation” traits are plants being engineered to have?

Answer 11

• Enhanced nutrition
• Improved taste
• Reduced browning
• Abiotic stress tolerance
• Nutrient use efficiency
• Environment (land reclamation)

Question 12

What is plant molecular farming? What sort of things are able to be produced this way?

Answer 12

The plant is engineered to produce a certain compound it wouldn’t normally produce then extracted. Can produce biopharmaceuticals like antibiotics, vaccines, antibodies. Can also produce nonpharmaceutical product like bioplastics, oils, biofuels, enzymes

Question 13

What is an herbicide?

Answer 13

A chemical that kills plants

Question 14

Why do we need to control weeds?

Answer 14

They compete with the crop plant and lower yields, as well as spread diseases and pests. Can contaminate harvests and lower the quality of the crop

Question 15

What 3 things are required for something to be an effective herbicide?

Answer 15

• Be able to kill weeds at low concentrations
• Be targeted so it kills the weed and not the crop
• Not toxic enough to cause harm to humans, animals, or the environment

Question 16

What two things are important to consider when measuring the toxicity of a substance?

Answer 16

Dose and exposure - how much for how long

Question 17

What is the genetically engineered trait of Roundup Ready canola?

Answer 17

Resistance to herbicides that contain glyphosate

Question 18

What is the transgene in Roundup Ready canola?

Answer 18

A gene that encodes EPSP synthase that isn’t inhibited by glyphosate. Enzyme is necessary to make certain amino acids

Question 19

What is the source of the transgene in Roundup Ready canola?

Answer 19

From a soil bacterium - Agrobacterium (strain CP4). The EPSP synthase produced has an alanine blocking the location where glyphosate would normally bind

Question 20

What is the current status of Roundup Ready canola in Canada?

Answer 20

It is widely grown across Canada with over a 90% adoption rate

Question 21

What is an insecticide?

Answer 21

A chemical that kills insects

Question 22

Why is it necessary to control insects?

Answer 22

They eat crops and damage them as well as spread diseases, which leads to lower yields and increased food wastage

Question 23

What makes an effective insecticide?

Answer 23

• effective at low concentrations
• Specific
• Reasonably safe for humans, animals, and the environment

Question 24

Why was the Bt potato created?

Answer 24

To control the Colorado Potato Beetle, a major pest of potatoes that is resistant to many insecticides

Question 25

What is the genetically engineered trait in Bt potatoes?

Answer 25

Expresses an endotoxin that binds to receptors in an insect’s stomach and causes them to die from leaky gut

Question 26

Why doesn’t the endotoxin expressed by Bt crops affect humans?

Answer 26

We don’t have the receptor, it is only present in insects

Question 27

What is the transgene in Bt potatoes?

Answer 27

The Cry gene

Question 28

What is the source of the transgene for Bt potatoes?

Answer 28

A soil bacterium - Bacillus trurigiensis

Question 29

What is the current status of the Bt potato?

Answer 29

They were withdrawn from the market

Question 30

What differences were there between the responses of the producers and the consumers in response to the Bt potatoes?

Answer 30

The potatoes were received favourably by the producers. Huge public backlash against the potato, restaurant chains refused to buy it so it stopped being grown because there was no buyers

Question 31

How have Bt crops influenced the use of insecticides?

Answer 31

Resulted in a dramatic decrease

Question 32

Does regulatory approval mean there will be a market for something?

Answer 32

No, regulatory approval is separate from the market. Even if the regulatory process deems the product to be safe, there is no guarantee it will be accepted favourably by the market

Question 33

Why were the rainbow papayas created?

Answer 33

The papaya ringspot virus was decimating the papaya industry in Hawaii, and spreading from island to island. Publicly funded research was launched to create a variety of papaya that was resistant to the virus in hopes of saving the industry in Hawaii

Question 34

What is the genetically engineered trait in the rainbow papayas?

Answer 34

Resistance to the papaya ringspot virus (PRSV). The plants could recognize when the virus was on them and mount a response against

Question 35

What is the transgene in rainbow papayas?

Answer 35

Expression of a coat protein of PRSV

Question 36

What is the source of the transgene in rainbow papayas?

Answer 36

PRSV

Question 37

What is the current status of the rainbow papaya?

Answer 37

Still being grown, have been able to reintroduce some of the conventional variety now that the virus is subdued enough

Question 38

Did the papaya industry in Hawaii fully recover after the introduction of the rainbow papaya?

Answer 38

No. One major importer of papaya was Japan, who has banned the import of GMOS

Question 39

What are the advantages of publicly funded research into GE crops?

Answer 39

Makes the product more accessible to farmers and alleviates concerns of corporations controlling the food supply

Question 40

What is a disadvantage of publicly funded research into GE crops?

Answer 40

Costs a lot and uses taxpayer dollars