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Golden Rice Risk Assessment

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Oliver Stengel

on 5 December 2012

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Transcript of Golden Rice Risk Assessment

05.12.12 Retinol = VITAMIN A How was it
Created? Genetic Engineering "E. Uredovora"
soil bacteria plasmid from Erwinia Uredovora

cut off with restriction enzymes Two beta-carotene biosynthesis genes are required: Phytoene synthase (psy) from daffodil

Phytoene desaturase (crt1) from E. uredovora plasmid + essential genes then inserted into agrobacterium,
which can infiltrate DNA into plants Rice embryos are put into a petri-dish with the agrobacteria that transfer the recombinant DNA to the rice's DNA. White rice gene Agrobacterium with recombinant DNA The rice is planted. Successful plants produce golden-colored rice grains rich in beta-carotene.
(Golden Rice 2: up to 37 ug/g dry rice) ... one of the leading crops in the world.
... feeds over 2/3 of the world's population.
(up to 80% of developing countries food-source!)
... can be grown in a wide variety of climates.
... is very easy to grow and simple seed-production BUT... WHY RICE? REFERENCES Rice genetically engineered to biosynthesize beta-carotene and help to combat vitamin A deficiency (VAD). "The Golden Rice Project"
Current status VAD? GR produces beta-carotene.
Our body converts b-carotene into retinol. two genes also removed with
restriction enzymes "Golden Rice 2" (Narcissus pseudonarcissus) 1. Wild Type
2. Daffodil psy (Np)
3. Maize psy (Zm) Exchange of the psy gene of daffodil to maize Ingo Potrykus (Swiss Federal Institute of Technology)

Peter Beyer (University of Freiburg) GR coordinated and continued at the IRRI

Phillipines (PhilRice)
field trials since 2008

commercial cultivation is expected
2013 in the Phillipines
2017 in Bangladesh
other target countries: India and Indonesia

at the moment: GR is being bred into local varieties that are popular in those countries (back-crossing) CONTROVERSY CURRENT STATUS RISKS interventions already exist

fighting poverty
sustainable farming
proven strategies for nutrition intervention
fortification of staple foods (e.g. flour, sugar)
diet diversification

significant reduction of VAD in recent years
vitamin fortification = effective strategy Environmental GR is the first GMO to be widely consumed by children ... yet no empirical data available

test done so far ...
no allergenic proteins
digestibility tests
taste differences to native rice
b-carotene bioavailability Health 1. International Rice Research Institute (IRRI)
will assess safety of the plants (int. standards)

2. Helen Keller International (HKI)
evaluate suitability for human consumption
providing required levels of vitamin A

Paine JA et al. (2005): Improving the nutritional value of Golden Rice through increased pro-vitamin A content, Nature Biotechnology 23/4: 482-87.

Pawlak J (2005): Increasing nutritional value of crops through micronutrient enhancement by transgenic means, MMG 445 eJournal 2005 1:1-5.

Potrykus I (2010): Food Opinion - Regulation must be revolutionized, Nature 466:561

Schaub P et al. (2005): Why Is Golden Rice Golden (Yellow) Instead of Red? Plant Physiology.

Tang G et al. (2012): b-Carotene in Golden Rice is as good as b-carotene in oil at providing vitamin A to children, Am J Clin Nutr 2012 96:658-64.

Then C (2010): Testbiotech opinion on EFSA’s draft guidance on the environmental risk assessment of genetically modified plants, Testbiotech e.V. Berlin.

Then C (2012): "Golden Lies" - The Seed Industry's Questionable Golden Rice Project, foodwatch report 2012, Testbiotech e.V. Berlin.

Further risk assessment studies of Golden Rice
(announced 2011) 190 million children suffer from VAD

670.000 children deaths/year

> 250.000 children blind/year (caused by VAD)

Aim of golden Rice:
... provide most of daily needed VitA
... reduce death rate about 25% Potrykus (2010)

general loosening of standards for the risk assessment of GMO

speed up market approval
+ limit expenses prevalent in developing countries

particularly children & pregnant women VAD can lead to:

- eye diseases blindness!

- skin diseases
- disorders of immune / reproductive systems
- growth deficiency in children ... mortality is attributable to VAD
... blindness is completely preventable! Will GR perform? stable amount of carotenoids produced in the field?

degradation rates (storage, cooking) under realistic conditions?

bioavailability in field conditions (e.g. malnutrition)? GR as the only way? ... majority of EU-member states call for stricter testing standards ... BUT commercial cultivation 2013 (IRRI)? risk assessment important
to foresee problems
helping the poorest
(GR in combination with existing approaches)

no risk to human health

possibility of cross-pollination is rare

trait "b-carotene" is not harming biodiversity

regulatory agencies & critics are responsible
for delays in the development of GR

"There are no significant differences between traditional breeding and genetic engineering – so why should genetic engineering be subject to risk assessment?" (Potrykus, 2010) Arguments What
think ? "A silent holocaust"? (Chassy, 2010) Malnutrition is a result of poverty 1980's rice = most important staple food

take care of varieties!

self pollinating, BUT pollen can flow uncontrolled:

outcrossing with local/conventional varieties
outcrossing with wild rice strains
confusion with conventional reddish rice varieties tests not done yet ...
animal feeding trials
substance analysis
subchronic toxicity
anti-nutritive effects 2009: trial test with 5 adult US-americans
conversion rate 4:1
50g uncooked rice could serve
60% of recommended VitA

2012: test on chinese school children
conversion rate as good as from supplements
controversy ("just a carrot") trojan horse

GR tested by the poor (“guinea pigs”)

criminal activity: "fake GR" (other varieties, yellow spices) Other critics WHO IS INVOLVED? internet-resources









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