GM Free Cymru

Golden Rice: Scientific Realities

Date Added to website 13th January 2014

GM Watch and GM-Free Cymru Contacts: Claire Robinson Brian John

Golden Rice (GR) is genetically engineered to contain increased levels of beta-carotene, a precursor of vitamin A (also known as provitamin A). The rice is claimed to help cure blindness and other illnesses caused by vitamin A deficiency in the Third World. It is also claimed that opposition to GR by environmentalists and anti-GMO activists has caused millions to die or go blind in the developing world.

However, the claims made for and about GR are factually incorrect and unscientific.

GR is still not ready

While there have been long delays in the development of GR since it was "invented" in 2000 (1), this has not been due to the activities of anti-GMO activists, but to basic R&D problems.

This is confirmed in a statement by the International Rice Research Institute, the main body working on the GR project (2). According to the Institute, the time frame for developing a new product is about 13 years, and GR is "still under development and evaluation". In September 2013 the IRRI expected GR to take another two years before it was ready.

GR is not needed

GR is an expensive and unproven 'solution' to a problem for which better solutions exist. It has swallowed millions in development money and yet is still not ready.

In contrast, World Health Organisation programs to combat vitamin A deficiency are cheap, already available – and proven to work. They focus on methods such as educating people to grow green leafy vegetables in kitchen gardens, encouraging breastfeeding of babies, and giving supplements and fortified foods when necessary. (3) Research by Dr Vandana Shiva's organization Navdanya in India has calculated that green leafy vegetables are up to 3500% richer in beta-carotene than GR. (4)

These programs only need modest funding to roll out more widely. They have the additional advantage of simultaneously treating other nutritional deficiencies, as these do not occur in isolation. For example, beta-carotene can only be absorbed by the body if the person eats enough fat. Will GR proponents give out dietary fat with the GR to those who need it?

Other problems with GR include:

1. Hidden Information on GR's Genetic Makeup. There has been no adequate characterisation of GR in the peer-reviewed literature (5). Where there is secrecy, there is mistrust.

2. Breeding Problems. The early varieties of Golden Rice were GR1 and GR2 -- both bred from Japonica rice varieties because of severe difficulties with breeding from Indica varieties. In the areas which are being initially targetted -- India, Sri Lanka, Bangladesh, Philippines -- the vast majority of the population eats Indica, not Japonica varieties. Testing of a GR Indica variety did not start until 2010, and besides the outdoor trials of GR2/Indica crosses in Philippines, we are not aware of any other outdoor trials. There are still no published data available as to the stability, uniformity, yields or beta-carotene levels of either the older or newer versions of GR.

3. Beta-carotene Persistence. No one knows how much beta-carotene will remain in GR over time when stored in normal domestic conditions. When some GR1 was sent in 2001 to scientists in Germany, they found that the level of beta-carotene was less than 1% of what it should have been. After cooking the level declined further, by 50%. This finding set back the project by many years.

4. Bioavailability. No one knows how "bioavailable" the beta-carotene in GR will prove. Only two published human feeding studies have been conducted to test this – a controversial child-feeding study published in 2012 and an earlier feeding study involving adults, published in 2009 (see point 7 below). Both these "proof of principle" studies fail to give information on whether GR would work in a real-life situation. For example, the GR samples were stored at -80 degrees C and -70 degrees C respectively, prior to their use in the trials. This was to delay any decline in beta-carotene levels. The studies gave no information as to the usefulness of GR in real domestic situations and in a typical diet. Also, the adult feeding study was designed to maximise the absorption of beta-carotene through the addition of 10% butter to the test diet – an unrealistic scenario with respect to the poor people of Asia.

5. Biofortification is Risky. GR is a "biofortified" product. But there are issues with "nutritional enhancement" and fortification. Due to differences between individuals (old and young, healthy and ill, male and female, overweight and undernourished), some people in the population will get too little of the nutrient and others too much. Overdosing on vitamin A has been linked to an increased risk of birth defects, and in the case of smokers to an increased cancer risk. (6)

6. No proof that GR is safe to eat. Genetic modification can result in novel toxins or allergens being created in plants, or changes in nutritional value. New toxins or allergens can appear even if the gene of interest is taken from a non-toxic source, since changes can happen after the gene is inserted into the new host plant. Such unexpected changes are difficult to detect without dedicated animal feeding safety trials. One potential hazard, as pointed out by Prof David Schubert of the Salk Institute in the USA, is associated with retinoic acid, a vitamin A derivative which can damage human fetuses and cause birth defects. (7) But no toxicology trials with animals have yet been carried out, in contravention of the Codex Alimentarius guidelines. Many scientists have complained about the manner in which the Golden Rice Humanitarian Board has simply assumed that GR is safe to eat, without having demonstrated it in studies. (8) After prolonged pressure, the IRRI announced in 2013 that animal feeding studies on mice were under way in an American laboratory. (9) But there has been no indication whether these studies are intended to demonstrate nutritional equivalence or safety. Until such studies have been published in the peer-reviewed literature, GR has not been proven safe to eat.

7. Unethical Trials on Humans. Even though GR has not been tested for unexpected toxins or allergens in animal feeding trials, the Golden Rice Humanitarian Board, in conjunction with Tufts University, has conducted three feeding experiments on humans. One included the use of children "without adequate vitamin A nutrition" (10). In 2009 a group of 32 scientists (11) complained to Tufts about this breach of medical ethics and the Nuremburg Code. When the research resulted in the publication of two papers (in 2009 and 2012), there was a furore in China due to the use of children in one experiment without informed consent. The revelation led to the sacking of three Chinese officials and the forced retirement of the lead researcher at Tufts.


The above points relate to the scientific issues surrounding GR. Other issues with GR relate to food sovereignty and security of supply, agricultural system preferences, and socio-economic and political factors.(12)

There also appear to be issues with corporate control and patenting, which throw into question claims that GR is a "public" product. The Sublicensing Agreement on the GR website states: "The inventors have assigned their exclusive rights to the Golden Rice technology to [GM giant] Syngenta… Syngenta retains commercial rights, although it has abandoned its plans to commercialise Golden Rice… Commercial rights of improvements to the technology go to Syngenta."(13)

The statement that Syngenta has "abandoned" its plans to commercialise GR is not legally binding. The firm could reverse this decision at any time it sees commercial potential in the product. And farmers who make "improvements" to GR strains could find themselves owing royalties to Syngenta.

In conclusion, GR is not a realistic solution to the problem of malnutrition and could well create further serious problems for the people who grow and eat it.


(1) Ye et al (2000) Engineering the Provitamin A (b-Carotene) Biosynthetic Pathway into (Carotenoid-Free) Rice Endosperm; Science, Vol 287. Patrick Moore (on the GoldenRiceNow web site) has accused Greenpeace of "crimes against humanity" over its opposition to genetically modified GR. Moore states that Greenpeace's "scientific blindness has led to the actual blindness of 8 million people, mostly children”. This is a serious and unsupportable accusation that bears no relation to the facts about GR. During January Moore is holding a series of "protests" and "forums" in European cities, with the help of Klaus Ammann and others and with the support of Europabio (the trade association for biotechnology companies), the John Innes Centre and other institutions and organizations with an interest in the promotion of GMO crops and foods.


(3) Tough Lessons From Golden Rice, by Martin Enserink, Science 25 April 2008: Vol. 320 no. 5875 pp. 468-471


(5) Patrick Moore's assertion that GR is "normal" apart from the insertion of two genes is a misrepresentation. (Video presentation)


(7) Schubert DR (2008). The problem with nutritionally enhanced plants. J Med Food 11(4): 601-605.