Using accelerated genetics to improve food: biological and social realities

Transcription

1 Using accelerated genetics to improve food: biological and social realities Professor Caitilyn Allen UW-Madison Dep t of Plant Pathology FRI-IFSH Food waste and sustainability: strategies to improve food safety, food security, and nutrition

2 Overview What are Accelerated Genetics? How Are GM Foods Produced? What are the Biological Risks of GM Foods? Disconnect Between Real & Perceived Risks of GM Foods How GM Foods Improve Sustainability & Reduce Waste What s Next? Undetectable gene editing with CRISPR

3 What are Accelerated Genetics? Genetically Modified Organisms. GMOs

4 What are Accelerated Genetics? Genetically Modified Organisms. Frankenfood!

5 How Are GM Foods Produced? The hardest part: identify a trait to modify Higher yield? Stress tolerance? Improved nutritional quality? Better processing traits? Longer shelf life?

6 Find gene(s) encoding the trait & move them into a crop

7 Using a gene gun to move DNA encoding the desired trait into plant cells

8 Each cell can give rise to a whole new plant A plant can be regenerated from one transformed cell Every cell in the plant contains the new DNA This plant is a GMO, or transgenic plant

9 Transgenic crops contain one or a few genes of known function Big Positives: Technical process is very fast Results are highly predictable Big Negatives: Regulatory process is costly & slow (can exclude nonprofits) Social acceptance: consumers are suspicious of GMOs

10 Social acceptance: consumers are suspicious of GM foods

11 If GM foods are controversial, why not just improve crops with traditional breeding?

12 Traditional breeding has already changed many crop plants dramatically

13 Traditional breeding has already changed many crop plants dramatically

14 Traditional breeding has already changed many crop plants dramatically not always for the better - Breeding for color and shelf-life has reduced flavor (tomatoes, apples) - Breeding for shipping tolerance has reduced nutrition (iron in spinach becomes nutritionally unavailable with increased oxalic acid)

15 If GM foods are controversial, why not just improve crops with traditional breeding? Traditional breeding is very slow (years to generations) Involves combining whole genomes of two parent plants Often introduces undesirable or unknown traits

16 Breeding using wild relatives can introduce: Disease resistance Insect resistance Better color, flavor Hardiness (to cold, drought...) Many other traits Wild relatives can also introduce toxins or allergens Ex: Wild potato relatives contain toxic alkaloids Need years of backcrosses to remove these traits Impossible if species are not closely related

17 Transgenic technology can change traits very precisely: Adding 2 bacterial genes to increase Vitamin A in Golden Rice Deleting 1 apple gene to make fruits that don t bruise or brown

18 History of GM Products in the US: 1982 FDA approves Humulin, human insulin synthesized by genetically engineered bacteria 1992 USDA approves Flavr Savr long shelf-life GM tomato 1995 EPA approves GM corn that makes BT organic insecticide 1996 Herbicide-tolerant Round Up-Ready crops introduced 2017 ~75% of the food in an average grocery store contains GMOs

19 Adoption of GM Crops in the US USDA-ARS Economic Research Service (2018) Recent Trends in GE Crops

20 What are the Biological Risks of GM Foods?

21 What are the Biological Risks of GM Foods? We have longitudinal population-wide data: Number of adverse effects, illnesses, or deaths associated with the widespread human or animal consumption of GM food over the past 22 years:

22 What are the Biological Risks of GM Foods? We have longitudinal population-wide data: Number of adverse effects, illnesses, or deaths associated with the widespread human and animal consumption of GM food over the past 22 years: - 0 -

23 Independent scientific analyses agree that current GMO crops are safe to eat: UN World Health Organization (WHO) U.S. National Academy of Sciences American Medical Association (AMA) American Association for the Advancement of Science (AAAS) The European Union French Académie des Sciences American Society for Cell Biology Union of German Academies of Sciences and Humanities Genetic Literacy Project (Non-profit, non-partisan) And many others.

24 Disconnect Between Real & Perceived Risks of GM Foods Food is personal; food & farming have great cultural significance Fear or suspicion of eugenics, and of large corporations (Monsanto Effect) Suspicion of new or unfamiliar technologies; the unfamiliar seems riskier than the familiar Confirmation bias: I trust organic foods, so I distrust GM crops

25 July 2016 US Congress passes watered-down law requiring labeling of GM foods With words:

26 July 2016 US Congress passes watered-down law requiring labeling of GM foods With QR Code:

27 Anti-GM food groups object:

28 The counter-label:

29 What do you think, Prof. Allen? Transgenic crop production is not inherently dangerous In many ways, it s just a faster and much more precise version of traditional crop breeding Like most technologies, it can be applied in dangerous or dumb ways Case-by-case regulation is needed

30 Anti-GM Food Attitudes Have Global Effects

31 Case Study #1 Bananas: World s 4th most important food crop Less than 10% are grown for export; 90% are locally consumed

32 Sub-Saharan Africa grows 1/3 of the world s bananas Bananas supply 30-60% of daily calories in Uganda, Rwanda & Burundi

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35 Bananas are also a major source of cash income

36 2001: a new banana disease appeared in Africa: Banana Xanthomonas Wilt, or BXW

37 Impact of BXW 53% production loss ~$8 billion over past 10 years Cooking banana prices up by 40% in Uganda

38 A dying banana plantation is a family catastrophe: Food insecurity Internal migration Kids leave school

39 An NGO, the IITA, made a BXW-resistant transgenic banana by adding two genes from sweet pepper These plants were fully resistant to BXW in the field (Tripathi 2014 Nature Biotechnology)

40 10 years after the first field tests, Ugandan farmers are still waiting for approval of diseaseresistant transgenic banana plants GM (left) & control (right) bananas Tripathi 2014 Nature Biotechnology

41 If people are going to die of hunger today, then we cannot be talking about the future. If GM is going to provide a solution, then as Africans we need to embrace it. -Arthur Kamenya, Ugandan banana farmer

42 Case Study #2: Papaya Trees resistant to Ringspot Virus (PRSV)

43 Case Study #2: Papaya Trees resistant to Ringspot Virus (PRSV) - the worst papaya disease - transmitted by aphid insects

44 PRSV appeared in Hawaii in 1992 Papaya yields fell 45% over the next 6 years

45 1998: Release of the genetically modified Rainbow papaya cultivar - immune to PRSV because it silences the virus coat protein gene

46 Traditional vs. GM papaya

47 Papaya trees exposed to PRSV parent transgenic

48 Hawaiian papaya yields recovering after introduction of PRSVresistant GM Rainbow trees

49 - 71% of Hawaiian papayas are now GM - Significantly decreased pesticide use - Consumers accept GM Papaya

50 What s Next? - Gene editing with CRISPR New technology changes just a few bits of DNA code: extremely precise April USDA: Crops created with gene editing are indistinguishable from products of crop breeding July EU court rules CRISPR plants must be regulated like conventional transgenic crops Major problem for regulators: CRISPR is undetectable

51 The first major CRISPR crop? Chocolate production employs 50 million people worldwide, generates >$100 billion But 20-30% of all cacao pods are lost to disease Climate change will reduce cacao yields M&M-Mars and U. California-Berkeley are using CRISPR to increase disease resistance & heat & drought tolerance of cacao trees Will consumers accept this chocolate?

52 Thanks for your attention!