Golden rice is a variety of rice (Oryza sativa) produced through genetic engineering to biosynthesize beta-carotene, a precursor of vitamin A, in the edible parts of the rice. It is intended to produce a fortified food to be grown and consumed in areas with a shortage of dietary vitamin A. Vitamin A deficiency causes xerophthalmia, a range of eye conditions from night blindness to more severe clinical outcomes such as keratomalacia and corneal scars, and permanent blindness. It also increases risk of mortality from measles and diarrhea in children. In 2013, the prevalence of deficiency was the highest in sub-Saharan Africa (48%; 25–75), and South Asia (44%; 13–79).
Although golden rice has met significant opposition from environmental and anti-globalisation activists, more than 100 Nobel laureates in 2016 encouraged use of genetically modified golden rice which can produce up to 23 times as much beta-carotene as the original golden rice.
In the 1990s, Peter Bramley discovered that a single phytoene desaturase gene (bacterial CrtI) can be used to produce lycopene from phytoene in GM tomato, rather than having to introduce multiple carotene desaturases that are normally used by higher plants. Lycopene is then cyclized to beta-carotene by the endogenous cyclase in golden rice. The scientific details of the rice were first published in 2000, the product of an eight-year project by Ingo Potrykus of the Swiss Federal Institute of Technology and Peter Beyer of the University of Freiburg.
The first field trials of golden rice cultivars were conducted by Louisiana State University Agricultural Center in 2004. Additional trials were conducted in the Philippines, Taiwan, and in Bangladesh (2015). Field testing provided an accurate measurement of nutritional value and enabled feeding tests to be performed. Preliminary results from field tests showed field-grown golden rice produces 4 to 5 times more beta-carotene than golden rice grown under greenhouse conditions.
As of 2018, breeders at the Philippine Rice Research Institute, the Bangladesh Rice Research Institute, and the Indonesian Centre for Rice Research were developing golden rice versions of existing rice varieties used with their local farmers, retaining the same yield, pest resistance, and grain qualities. Golden rice seeds may cost farmers the same as other rice varieties.
In 2018, Canada and the United States approved golden rice, with Health Canada and the US Food and Drug Administration (FDA) declaring it safe for consumption. This followed a 2016 decision where the FDA had ruled that the beta-carotene content in golden rice did not provide sufficient amounts of vitamin A for US markets. Health Canada declared that golden rice would not affect allergies, and that the nutrient contents were the same as in common rice varieties, except for the intended high levels of provitamin A.
In 2019, golden rice was approved for use as human food and animal feed or for processing in the Philippines. On 21 July 2021, the Philippines became the first country to officially issue the biosafety permit for commercially propagating vitamin A-infused golden rice. The approval came as the first commercial propagation authorisation of genetically engineered rice in South and Southeast Asia. As a result of the permission, golden rice can be grown on a commercial scale in accordance with the terms and conditions specified by the Philippines government.
Golden rice was created by transforming rice with two beta-carotene biosynthesis genes:
- psy (phytoene synthase) from daffodil (Narcissus pseudonarcissus)
- crtI (phytoene desaturase) from the soil bacterium Erwinia uredovora
(The insertion of a lcy (lycopene cyclase) gene was thought to be needed, but further research showed it is already produced in wild-type rice endosperm.)
The psy and crtI genes were transferred into the rice nuclear genome and placed under the control of an endosperm-specific promoter, so that they are only expressed in the endosperm. The exogenous lcy gene has a transit peptide sequence attached, so it is targeted to the plastid, where geranylgeranyl diphosphate is formed. The bacterial crtI gene was an important inclusion to complete the pathway, since it can catalyse multiple steps in the synthesis of carotenoids up to lycopene, while these steps require more than one enzyme in plants. The end product of the engineered pathway is lycopene, but if the plant accumulated lycopene, the rice would be red. Recent analysis has shown the plant's endogenous enzymes process the lycopene to beta-carotene in the endosperm, giving the rice the distinctive yellow colour for which it is named. The original golden rice was called SGR1, and under greenhouse conditions it produced 1.6 µg/g of carotenoids.
Golden Rice 2
In 2005, a team of researchers at Syngenta produced Golden Rice 2. They combined the phytoene synthase (psy) gene from maize with crtl gene from the original golden rice. Golden Rice 2 produces 23 times more carotenoids than golden rice (up to 37 µg/g) because psy gene of maize is the most effective gene for carotenoid synthesis, and preferentially accumulates beta-carotene (up to 31 µg/g of the 37 µg/g of carotenoids).
Vitamin A deficiency
The research that led to Golden Rice was conducted with the goal of helping children who suffer from vitamin A deficiency (VAD). Estimates show that around 1.02 billion people are severely affected by micronutrient deficiencies globally, with vitamin A to be the most deficient nutrient in the body. In 2012, the World Health Organization reported that about 250 million preschool children are affected by VAD, and that providing those children with vitamin A could prevent about a third of all under-five deaths, which amounts to up to 2.7 million children that could be saved from dying unnecessarily. The World Health Organization has classified vitamin A deficiency as a public health problem affecting about one third of children aged 6 to 59 months in 2013, with the highest rates in sub-Saharan Africa (48 per cent) and South Asia (44 per cent).
VAS programs began in the 1990s in response to evidence demonstrating the association between VAD and increased childhood mortality. Between 1990 and 2013, more than 40 efficacy studies of VAS in children 6–59 months of age were conducted, and two systematic reviews and meta-analyses have concluded that VA supplements can considerably reduce mortality and morbidity during childhood. As of 2017, more than 80 countries worldwide are implementing universal VA supplementation (VAS) programs targeted to children 6–59 months of age through semi-annual national campaigns. Periodic, high-dose vitamin A supplementation is a proven, low-cost intervention which has been shown to reduce all-cause mortality by 12 to 24 per cent, and is therefore an important program in support of efforts to reduce child mortality. However, UNICEF and a number of NGOs involved in supplementation note more frequent low-dose supplementation is preferable.
As many children in VAD-affected countries rely on rice as a staple food, genetic modification to make rice produce the vitamin A precursor beta-carotene was seen as a simple and less expensive alternative to ongoing vitamin supplements or an increase in the consumption of green vegetables or animal products. Initial analyses of the potential nutritional benefits of golden rice suggested consumption of golden rice would not eliminate the problems of vitamin A deficiency, but could complement other supplementation. Golden Rice 2 contains sufficient provitamin A to provide the entire dietary requirement via daily consumption of some 75g per day.
Vitamin A deficiency is usually coupled to an unbalanced diet. Since carotenes are hydrophobic, sufficient fat must be present in the diet for golden rice (or most other vitamin A supplements) to alleviate vitamin A deficiency. Moreover, this claim referred to an early cultivar of Golden Rice; one bowl of the latest version provides 60% of RDA for healthy children. The RDA levels advocated in developed countries are far in excess of the amounts needed to prevent blindness.
In 2009, results of a clinical trial of golden rice with adult volunteers concluded that "beta-carotene derived from golden rice is effectively converted to vitamin A in humans". A summary for the American Society for Nutrition suggested that "Golden Rice could probably supply 50% of the Recommended Dietary Allowance (RDA) of vitamin A from a very modest amount – perhaps a cup – of rice, if consumed daily. This amount is well within the consumption habits of most young children and their mothers". Beta-carotene is found and consumed in many nutritious foods eaten around the world, including fruits and vegetables. Beta-carotene in food is a safe source of vitamin A.
A 2012 study showed that the beta-carotene produced by golden rice is as effective as beta-carotene in oil at providing vitamin A to children. The study stated that "recruitment processes and protocol were approved". However, in 2015, the journal retracted the study, claiming that the researchers had acted unethically when providing Chinese children golden rice without their parents' consent.
Golden rice improves vitamin A intake and may reduce vitamin A deficiency among women and children. Food derived from golden rice varieties is as safe as food derived from conventional rice varieties.
Critics of genetically engineered crops have raised various concerns. An early issue was that Golden Rice originally did not have sufficient beta-carotene content. This problem was solved by the advancing of GR2E event. The speed at which beta-carotene degrades once the rice is harvested, and how much remains after cooking are contested. However, a 2009 study concluded that beta-carotene from golden rice is effectively converted into vitamin A in humans.
Greenpeace opposes the use of any patented genetically modified organisms in agriculture and opposes the cultivation of golden rice, claiming it will open the door to more widespread use of GMOs. The International Rice Research Institute (IRRI) has emphasised the non-commercial nature of their project, stating that "None of the companies listed ... are involved in carrying out the research and development activities of IRRI or its partners in Golden Rice, and none of them will receive any royalty or payment from the marketing or selling of golden rice varieties developed by IRRI."
Vandana Shiva, an Indian anti-GMO activist, argued the problem was not the plant per se, but potential issues with loss of biodiversity. Shiva argued that golden rice proponents were obscuring the limited availability of diverse and nutritionally adequate food. Other groups argued that a varied diet containing foods rich in beta-carotene such as sweet potato, leaf vegetables and fruit would provide children with sufficient vitamin A. However, Keith West of Johns Hopkins Bloomberg School of Public Health has said that foodstuffs containing vitamin A are often unavailable, only available at certain seasons, or are too expensive for poor families to obtain.
In 2008, WHO malnutrition expert Francesco Branca cited the lack of real-world studies and uncertainty about how many people will use golden rice, concluding "giving out supplements, fortifying existing foods with vitamin A, and teaching people to grow carrots or certain leafy vegetables are, for now, more promising ways to fight the problem". Author Michael Pollan, who had criticized the product in 2001, being unimpressed by the benefits, expressed support for the continuation of the research in 2013.
In 2012, controversy surrounded a study published in The American Journal of Clinical Nutrition. The study, involving feeding GM rice to children from 6 to 8 years old in China, was later found to have violated human research rules of both Tufts University and the federal government. Subsequent reviews found no evidence of safety problems with the study, but found issues with insufficient consent forms, unapproved changes to study protocol, and lack of approval from a China-based ethics review board. Additionally, the GM rice used was brought into China illegally.
The Bill and Melinda Gates Foundation supports the use of genetically modified organisms in agricultural development and supports the International Rice Research Institute in developing golden rice. In June 2016, 107 Nobel laureates signed a letter urging Greenpeace and its supporters to abandon their campaign against GMOs, and against golden rice in particular.
In May 2018, the U.S. Food and Drug Administration approved the use of golden rice for human consumption, stating: "Based on the information IRRI has presented to FDA, we have no further questions concerning human or animal food derived from GR2E rice at this time." This marks the fourth national health organisation to approve the use of golden rice in 2018, joining Australia, Canada and New Zealand who issued their assessments earlier in the year.
In December 2021, an opinion piece in Proceedings of the National Academy of Sciences of the United States of America called on regulators to "allow Golden Rice to save lives", which the authors say has been delayed due to "fear and false accusations", leading to estimated 266'000 lives lost per year due to vitamin A deficiency.
On August 8, 2013, an experimental plot of Golden Rice being developed by IRRI and DA-PhilRice in Camarines Sur province of the Philippines was uprooted by protesters. British author Mark Lynas reported in Slate that the vandalism was carried out by a group of activists led by Kilusang Magbubukid ng Pilipinas (KMP) (unofficial translation: Farmers' Movement of the Philippines).
A recommendation was made that golden rice be distributed free to subsistence farmers. Free licenses for developing countries were granted quickly due to the positive publicity that golden rice received, particularly in Time magazine in July 2000. Monsanto Company was one of the companies to grant free licences for related patents owned by the company. The cutoff between humanitarian and commercial use was set at US$10,000. Therefore, as long as a farmer or subsequent user of golden rice genetics would not make more than $10,000 per year, no royalties would need to be paid. In addition, farmers would be permitted to keep and replant seed.
- Kettenburg AJ, Hanspach J, Abson DJ, Fischer J (2018). "From disagreements to dialogue: unpacking the Golden Rice debate". Sustain Sci. 13 (5): 1469–82. doi:10.1007/s11625-018-0577-y. PMC 6132390. PMID 30220919.
- Ye X, Al-Babili S, Klöti A, Zhang J, Lucca P, Beyer P, Potrykus I (January 2000). "Engineering the provitamin A (beta-carotene) biosynthetic pathway into (carotenoid-free) rice endosperm". Science. 287 (5451): 303–5. Bibcode:2000Sci...287..303Y. doi:10.1126/science.287.5451.303. PMID 10634784.
- Stevens GA, Bennett JE, Hennocq Q, Lu Y, De-Regil LM, et al. (September 2015). "Trends and mortality effects of vitamin A deficiency in children in 138 low-income and middle-income countries between 1991 and 2013: a pooled analysis of population-based surveys". Lancet Glob Health. 3 (9): e528–36. doi:10.1016/S2214-109X(15)00039-X. PMID 26275329. S2CID 4671055.
- Paine JA, Shipton CA, Chaggar S, Howells RM, Kennedy MJ, et al. (April 2005). "Improving the nutritional value of Golden Rice through increased pro-vitamin A content". Nat Biotechnol. 23 (4): 482–7. doi:10.1038/nbt1082. PMID 15793573. S2CID 632005.
- Tang G, Qin J, Dolnikowski GG, Russell RM, Grusak MA (June 2009). "Golden Rice is an effective source of vitamin A". Am J Clin Nutr. 89 (6): 1776–83. doi:10.3945/ajcn.2008.27119. PMC 2682994. PMID 19369372.
- Datta SK, Datta K, Parkhi V, Rai M, Baisakh N, et al. (2007). "Golden rice: introgression, breeding, and field evaluation". Euphytica. 154 (3): 271–78. doi:10.1007/s10681-006-9311-4. S2CID 39594178.
- "FAQ: Who invented Golden Rice and how did the project start?". Goldenrice.org.
- Romer, S.; Fraser, P.D.; Kiano, J.W.; Shipton, C.A.; Misawa, N; Schuch, W.; Bramley, P.M. (2000). "Elevation of provitamin A content of transgenic tomato plants". Nature Biotechnology. 18 (6): 666–69. doi:10.1038/76523. PMID 10835607. S2CID 11801214.
- "The Science of Golden Rice". Retrieved 11 July 2013.
- LSU AgCenter Communications (2004). "'Golden Rice' Could Help Reduce Malnutrition". Archived from the original on 28 September 2007.
- Ahmad, Reaz (8 October 2015). "Bangladeshi scientists ready for trial of world's first 'Golden Rice'". The Daily Star. Retrieved 15 December 2015.
- "Testing the performance of Golden Rice". Goldenrice.org. 29 August 2012. Retrieved 26 August 2013.
- "Golden Rice". International Rice Research Institute. 3 December 2018. Retrieved 21 August 2021.
- Coghlan, Andy (30 May 2018). "GM golden rice gets approval from food regulators in the US". New Scientist. Retrieved 21 August 2021.
- "Consultation Programs on Food from New Plant Varieties". Center for Food Safety and Applied, US Food and Drug Administration. 1 February 2021. Retrieved 21 August 2021.
- "Provitamin A Biofortified Rice Event GR2E (Golden Rice)". Health Canada. 16 March 2018. Retrieved 21 August 2021.
- "Philippines approves Golden Rice for direct use as food and feed, or for processing". International Rice Research Institute. 18 December 2019. Retrieved 21 August 2021.
- Talavera, Catherine. "Philippines OKs GMO 'golden rice'". Philstar.com. Retrieved 21 August 2021.
- "Filipinos soon to plant and eat Golden Rice". Philippine Rice Research Institute. 23 July 2021. Retrieved 21 August 2021.
- Hirschberg, J. (2001). "Carotenoid biosynthesis in flowering plants". Current Opinion in Plant Biology. 4 (3): 210–18. doi:10.1016/S1369-5266(00)00163-1. PMID 11312131.
- Schaub, P.; Al-Babili, S; Drake, R; Beyer, P (2005). "Why Is Golden Rice Golden (Yellow) Instead of Red?". Plant Physiology. 138 (1): 441–50. doi:10.1104/pp.104.057927. PMC 1104197. PMID 15821145.
- Paine, Jacqueline A.; Shipton, Catherine A.; Chaggar, Sunandha; Howells, Rhian M.; Kennedy, Mike J.; Vernon, Gareth; Wright, Susan Y.; Hinchliffe, Edward; Adams, Jessica L.; Silverstone, Aron L.; Drake, Rachel (2005). "Improving the nutritional value of Golden Rice through increased pro-vitamin a content". Nature Biotechnology. 23 (4): 482–487. doi:10.1038/nbt1082. PMID 15793573. S2CID 632005.
- Wirth JP, Petry N, Tanumihardjo SA, Rogers LM, McLean E, Greig A, Garrett GS, Klemm RD, Rohner F (February 2017). "Vitamin A Supplementation Programs and Country-Level Evidence of Vitamin A Deficiency". Nutrients. 9 (3): 190. doi:10.3390/nu9030190. PMC 5372853. PMID 28245571.
- "Vitamin A Deficiency". goldenrice.org. Retrieved 21 August 2021.
- "Vitamin A Deficiency in Children". UNICEF DATA. Retrieved 21 August 2021.
- Dawe, D.; Robertson, R.; Unnevehr, L. (2002). "Golden rice: what role could it play in alleviation of vitamin A deficiency?". Food Policy. 27 (5–6): 541–60. doi:10.1016/S0306-9192(02)00065-9.
- Zimmerman, R.; Qaim, M. (2004). "Potential health benefits of Golden Rice: a Philippine case study". Food Policy. 29 (2): 147–68. doi:10.1016/j.foodpol.2004.03.001. Archived from the original on 6 January 2009. Retrieved 13 May 2009.
- Harmon, Amy (24 August 2013). "Golden Rice: Lifesaver?". The New York Times. ISSN 0362-4331. Retrieved 21 August 2021.
- Paine, Jacqueline A.; Shipton, Catherine A.; Chaggar, Sunandha; Howells, Rhian M.; Kennedy, Mike J.; Vernon, Gareth; Wright, Susan Y.; Hinchliffe, Edward; Adams, Jessica L.; Silverstone, Aron L.; Drake, Rachel (April 2005). "Improving the nutritional value of Golden Rice through increased pro-vitamin A content". Nature Biotechnology. 23 (4): 482–487. doi:10.1038/nbt1082. ISSN 1546-1696. PMID 15793573. S2CID 632005.
- Tang, G.; Qin, J.; Dolnikowski, G. G.; Russell, R. M.; Grusak, M. A. (2009). "Golden Rice is an effective source of vitamin A" (PDF). The American Journal of Clinical Nutrition. 89 (6): 1776–1783. doi:10.3945/ajcn.2008.27119. PMC 2682994. PMID 19369372.
- "Researchers Determine That Golden Rice Is an Effective Source of Vitamin A" (PDF). American Society of Nutrition.
- Grune, T.; Lietz, G.; Palou, A.; Ross, A. C.; Stahl, W.; Tang, G.; Thurnham, D.; Yin, S. A.; Biesalski, H. K. (2010). "Beta-carotene is an important vitamin a source for humans". The Journal of Nutrition. 140 (12): 2268S–2285S. doi:10.3945/jn.109.119024. PMC 3139236. PMID 20980645.
- Tang, G.; Hu, Y.; Yin, S. A.; Wang, Y.; Dallal, G. E.; Grusak, M. A.; Russell, R. M. (2012). "Β-Carotene in Golden Rice is as good as β-carotene in oil at providing vitamin a to children" (PDF). The American Journal of Clinical Nutrition. 96 (3): 658–664. doi:10.3945/ajcn.111.030775. PMC 3417220. PMID 22854406.
- "Retraction of Tang G, Hu y, Yin S-a, Wang y, Dallal GE, Grusak MA, and Russell RM. β-Carotene in Golden Rice is as good as β-carotene in oil at providing vitamin a to children. Am J Clin Nutr 2012;96:658–64". The American Journal of Clinical Nutrition. 102 (3): 715. 2015. doi:10.3945/ajcn.114.093229. PMC 4548169. PMID 26224301.
- Weintraub, Karen (17 August 2015). "Ethics in question, Tufts researcher's paper retracted". The Boston Globe. Retrieved 30 January 2023.
- De Moura, Fabiana F; Moursi, Mourad; Donahue Angel, Moira; Angeles-Agdeppa, Imelda; Atmarita, Atmarita; Gironella, Glen M; Muslimatun, Siti; Carriquiry, Alicia (September 2016). "Biofortified β-carotene rice improves vitamin A intake and reduces the prevalence of inadequacy among women and young children in a simulated analysis in Bangladesh, Indonesia, and the Philippines". The American Journal of Clinical Nutrition. 104 (3): 769–775. doi:10.3945/ajcn.115.129270. ISSN 0002-9165. PMC 4997296. PMID 27510534.
- Oliva, Norman; Florida Cueto-Reaño, Maria; Trijatmiko, Kurniawan R.; et al. (28 January 2020). "Molecular characterization and safety assessment of biofortified provitamin A rice". Scientific Reports. 10 (1): 1376. Bibcode:2020NatSR..10.1376O. doi:10.1038/s41598-020-57669-5. ISSN 2045-2322. PMC 6987151. PMID 31992721.
- Then, Christoph (2009). "The campaign for genetically modified rice is at the crossroads: A critical look at Golden Rice after nearly 10 years of development" (PDF). Foodwatch in Germany. S2CID 113405617.
- Tang, Guangwen; Qin, Jian; Dolnikowski, Gregory G; Russell, Robert M; Grusak, Michael A (1 June 2009). "Golden Rice is an effective source of vitamin A". The American Journal of Clinical Nutrition. 89 (6): 1776–1783. doi:10.3945/ajcn.2008.27119. ISSN 0002-9165. PMC 2682994. PMID 19369372.
- "Genetic Engineering". Greenpeace.
"Golden Rice: All glitter, no gold". Greenpeace. 16 March 2005.
- "All that Glitters is not Gold: The False Hope of Golden Rice" (PDF). Greenpeace. 2005. Archived from the original (PDF) on 1 August 2013.
- "FAQ: Are private companies involved in the Golden Rice project?". IRRI. 2014. Archived from the original on 27 July 2016.
- Shiva, Vandana (29 June 2000). "The "Golden Rice" Hoax – When Public Relations replaces Science". Online.sfsu.edu. Retrieved 26 August 2013.
- "Golden Rice and Vitamin A Deficiency". Friends of the Earth. Archived from the original on 2 June 2016.
- Norton, Amy (15 August 2012). "Genetically modified rice a good vitamin A source". Reuters. Retrieved 20 August 2012.
- Enserink, M. (2008). "Tough Lessons From Golden Rice". Science. 320 (5875): 468–71. doi:10.1126/science.320.5875.468. PMID 18436769. S2CID 206580074.
- Andrew Revkin (1 September 2013). "From Lynas to Pollan, Agreement that Golden Rice Trials Should Proceed". The New York Times.
- Tang, Guangwen; Hu, Yuming; Yin, Shi-an; Wang, Yin; Dallal, Gerard E; Grusak, Michael A; Russell, Robert M (1 September 2012). "β-Carotene in Golden Rice is as good as β-carotene in oil at providing vitamin A to children". The American Journal of Clinical Nutrition. 96 (3): 658–664. doi:10.3945/ajcn.114.093229. PMC 4548169. PMID 26224301. (Retracted)
- Enserink, Martin (18 September 2013). "Golden Rice Not So Golden for Tufts". Science Magazine. Retrieved 1 April 2020.
- Qiu, Jane (10 December 2012). "China sacks officials over Golden Rice controversy". Nature. Retrieved 1 April 2020.
- "Agricultural Development Golden Rice". Archived from the original on 3 February 2016. Retrieved 3 February 2016.
- "Laureates Letter Supporting Precision Agriculture (GMOs)". Retrieved 5 July 2016.
- Achenbach, Joel (30 June 2016). "107 Nobel laureates sign letter blasting Greenpeace over GMOs". Washington Post. Retrieved 11 July 2016.
- "US FDA approves GMO Golden Rice as safe to eat | Genetic Literacy Project". geneticliteracyproject.org. 29 May 2018. Retrieved 30 May 2018.
- "Golden Rice meets food safety standards in three global leading regulatory agencies". International Rice Research Institute – IRRI. Retrieved 30 May 2018.
- Wu, F.; Wesseler, J.; Zilberman, D.; Russell, R. M.; Chen, C.; Dubock, A. C. (2021). "Opinion: Allow Golden Rice to save lives". Proceedings of the National Academy of Sciences of the United States of America. 118 (51). doi:10.1073/pnas.2120901118. PMC 8713968. PMID 34911769.
- Slezak, Michael (9 August 2013). "Militant Filipino farmers destroy Golden Rice GM crop". New Scientist. Retrieved 21 August 2021.
- Lynas, Mark (26 August 2013). "Anti-GMO Activists Lie About Attack on Rice Crop (and About So Many Other Things)". Slate Magazine. Retrieved 21 August 2021.
- Potrykus, I. (2001). "Golden Rice and Beyond". Plant Physiology. 125 (3): 1157–61. doi:10.1104/pp.125.3.1157. PMC 1539367. PMID 11244094.
- Nash, J. Madeleine (31 July 2000). "This Rice Could Save a Million Kids a Year". Time. Retrieved 12 June 2014.
- Dobson, Roger (2000), "Royalty-free licenses for genetically modified rice made available to developing countries", Bulletin of the World Health Organization, 78 (10): 1281, PMC 2560613, PMID 11100623.
- "Golden Rice Project". Frequently asked questions. Golden rice. 13 October 2004. Retrieved 26 August 2013.