Is Golden Rice the Only Way to Provide Vitamin A to People in Developing Countries?

Vitamin A deficiency, along with iron and zinc deficiencies, pose the greatest public health consequences of all micronutrient deficiencies. Vitamin A deficiency is most common in young children and pregnant women and can lead to blindness, susceptibility to infectious diseases, and death (1). The Food and Agricultural Organization and the United Nations have developed different strategies to overcome deficiency of vitamin A, including dietary diversification, food fortification, and vitamin supplementation. When applied, there has been varying success in different regions of the developing world with the various approaches, e.g., distribution of vitamin A pills in Nepal (2), the fortification of sugar with vitamin A in Guatemala (3), and gardening projects in Bangladesh and Thailand (4). All these efforts required continuous public education and financial support from the public and private sector. For example, vitamin A fortification of sugar was temporarily suspended owing to an economic downturn that increased vitamin A prices and at that point vitamin A deficiency reappeared (4).

Despite these various efforts, ∼250,000 to 500,000 children deficient in vitamin A become blind each year; half of them die within twelve months (5). Recent studies indicate that biofortification, i.e., incorporating micronutrients into food, has the potential to control deficiencies and is cost-effective and efficient compared with alternative public health and agricultural measures when coupled with other micronutrient interventions (6). To develop a biofortification strategy to address vitamin A deficiency, researchers developed the first variety of Golden Rice (GR1), a GE variety with increased levels of β- carotene, a precursor to vitamin A, compared with non-GE rice (7). The rice contained three new genes, two from daffodil (Narcissus pseudonarcissus) and one from a bacterium (Erwinia uredovora). In 2005 the development of a new Golden Rice variety, GR2, was published; in GR2 a maize gene is substituted for the daffodil genes, boosting β-carotene levels to 37 μg/g—estimated to provide 50% of a child’s RDA of vitamin A in 72 g of dry GR2 rice (8). However, the actual impact of this rice also depends on several other variables, e.g., uptake and conversion to vitamin A, amount consumed, bioavailability, effects of cooking, and consumer acceptance (9).

The GR1 and GR2 rice varieties are in use in breeding programs in the Philippines, India, Bangladesh, China, and Vietnam; the use of Golden Rice is being governed by the Golden Rice Humanitarian Board and is based on full regulatory compliance (G. Berry, personal communication). Although perhaps not legally needed, because often no intellectual property restrictions exist in these countries on commonly employed genes [e.g., 35S promoter, hygromycin resistance gene (10)], all companies with patents applying to Golden Rice licensed them at no charge for use in resource-poor countries.

Golden Rice might increase vitamin A sufficiency for people in areas difficult to reach with other vitamin A distribution efforts or for people with limited opportunities to grow or purchase sufficient amounts of fresh vegetables or fruits. Golden Rice will not be the single solution to vitamin A deficiency worldwide, but it is another tool that can be used in public health programs to combat vitamin A deficiency.

References:

1. World Health Org. (WHO). 2007. Micronutrients. http://www.who.int/nutrition/topics/micronutrients/en/. Last accessed 2011-12-9. PDF

2. UNICEF. 2001. A million children saved through vitamin A supplementation. http://www.unicef.org/newsline/01pr13.htm. Last accessed 2011-12-9. PDF

3. Arroyave G, Aguilar JR, Flores M, Guzman MA. 1995. Fortification of sugar with vitamin A. UN Univ. 192(Chapter 7):1–82

4. Underwood BA, Smitasiri S. 1999. Micronutrient malnutrition: Policies and programs for control and their implications. Annu. Rev. Nutr. 19:303–24

5. World Health Org. (WHO). 2007. Micronutrient deficiencies, Vitamin A deficiency. http://www.who.int/nutrition/topics/vad/en/. Last accessed 2011-12-9. PDF

6. Stein AJ. 2006. Micronutrient malnutrition and the impact of modern plant breeding on public health in India: How cost-effective is biofortification? Göttingen: Cuvillier Verlag

7. Ye X, Al-Babili S, Kloti A, Zhang J, Lucca P, et al. 2000. Engineering the provitamin A (β-carotene) biosynthetic pathway into (carotenoid-free) rice endosperm. Science 287:303–5

8. Paine JA, Shipton CA, Chaggar S, Howells RM, Kennedy MJ, et al. 2005. Improving the nutritional value of Golden Rice through increased provitamin A content. Nat. Biotechnol. 23:429–30
Seminal paper describing second generation, nutritionally enhanced Golden Rice.

9. Bouis H. 2004. Hidden hunger: the role of nutrition, fortification and biofortification. Presented atWorld Food Prize Int. Symp., Des Moines, IA

10. Binenbaum E, Nottenburg C, Pardey PG, Wright BD, Zambrano P. 2000. South-north trade, intellectual property jurisdictions, and Freedom to Operate in agricultural research on staple crops. Environ. Prod. Technol. Div., Int. Food Policy Res. Inst. Discuss. Pap. No. 70

Updated 2/16/12