How is golden rice modified

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For those interested in scientific details about carotenoids, here's a scientific review that covers the mechanisms controlling 1 the first committed step in phytoene biosynthesis, 2 flux through the branch to synthesis of a- and b-carotenes and 3 metabolic feedback signalling within and between the carotenoid, MEP and ABA pathways; by Christopher Cazzonelli, published in the journal Functional Plant Biology in with permission from CSIRO Publishing.

About Contact Site map Links. The Science of Golden Rice. Several known pathways branch off at this point, forming biologically important molecules, such as abscisic acid and strigolactones Carotenoids and their derivatives include a vast number of molecules and accordingly a great number of enzymes and cofactors. The underlying science in more detail All plant tissues that accumulate high levels of carotenoids have mechanisms for carotenoid sequestration, including crystallisation, oil deposition, membrane proliferation or protein-lipid sequestration.

The image clearly shows the progress made since the proof-of-concept stage of Golden Rice. J Exp Bot Bartley G, Kumle A, Beyer P, Scolnik P Functional analysis and purification of enzymes for carotenoid biosynthesis expressed in photosynthetic bacteria.

Methods Enzymol Bartley GE, Scolnik PA, Beyer P Two Arabidopsis thaliana carotene desaturases, phytoene desaturase and zeta-carotene desaturase, expressed in Escherichia coli , catalyze a poly-cis pathway to yield pro-lycopene.

Eur J Biochem J Nutr S J Biol Chem Beyer P, Mayer M, Kleinig H Molecular oxygen and the state of geometric isomerism of intermediates are essential in the carotene desaturation and cyclization reactions in daffodil chromoplasts. Plant J Plant Physiol Plant Physiology Plant Cell Mayer M, Beyer P, Kleinig H Quinone compounds are able to replace molecular oxygen as terminal electron acceptor in phytoene desaturation in chromoplasts of Narcissus pseudonarcissus L.

This principle states that if a product of modern biotechnology poses a possible risk to human health or the environment, then it is prudent to restrict or prevent the introduction or use of that product or technology, even if the magnitude or nature of the risk is uncertain, speculative, scientifically unproven, or even unknown.

Although it may have been benign in its intent, the effect of the principle has been to slow the pace of biotechnology research and development—and in some cases even to halt it, at least temporarily, at multiple times during the research and development process.

In the case of Golden Rice, the combined result of these three factors—the scientific difficulty of the project, the slow and stately rate of plant growth and reproduction, and a body of stifling government regulations governing biotechnology research and development—was to prolong the incubation time of a food that, absent externally imposed government restrictions, could otherwise be saving the sight and lives of millions of people.

The story of Golden Rice thus makes for a sad and maddening tale of scientists being repeatedly thwarted in their attempts to invent, improve, breed, field-test, and disseminate a potentially lifesaving food.

It is an understatement to say that their task was daunting. There was no assurance when they started out that what they contemplated was even technologically possible, since it had never been done before. But the two men were highly motivated by the horrors of persistent vitamin A deficiency in developing countries, and they viewed their work as a calling—one from which they would not be deterred.

It took almost a decade of laboratory experimentation to invent Golden Rice, but by , Potrykus, Beyer, and a group of colleagues finally succeeded. Once they accomplished that small but powerful technological trick, the inventors naively imagined that the hard part was now behind them.

Little did they know that the most difficult tasks still lay ahead. Once they had their initial proof-of-concept rice in hand, the inventors moved swiftly to develop Golden Rice further, first to improve the product and then to make it available, for free, to poor farmers in developing countries.

Zeneca later merged with the Swiss-based company Syngenta, but the terms of the original arrangement remained unchanged. On Feb. Around the same time, the Cartagena Protocol on Biosafety was making waves. The protocol had been adopted in the year by more than nations, including members of the European Union but neither the United States nor Canada.

The agreement contained one version of the precautionary principle. Exactly what that principle, which focused on avoiding unknown risks, meant in practice was not immediately clear. It is more of an ideal, a standard of perfection to be aimed at, than a real-world guide to action or public policy. The simple transfer of seeds from one country to another became a major logistical problem. Golden Rice was unique among genetically engineered foods, and the properties that made it different also made it immune to many of the conventional criticisms of GMOs.

Golden Rice was not invented for profit, and after , when Syngenta renounced all commercial interest in the rice, it would no longer be developed for profit. The rice would benefit the poor and disadvantaged, not modern, multinational corporations. It would be given free of charge to subsistence farmers who can save seeds and plant them from one harvest to the next, without restriction or payment of fees or royalties.

As genetically modified crops would have to be grown, there are concerns about the effect they would have on the surrounding environment. Could the crops negatively impact biodiversity? A possible threat to biodiversity arises when genetically modified crops breed with wild species.

Another issue concerns the spreading, escaping, or crossing of genes from genetically modified crops. This could create unwanted pesticide or herbicide resistance. As with human safety concerns, there is a possibility that other animals that eat genetically modified crops will be affected. Studies of the long-term impacts of planting and consuming golden rice have been minimal.

Even though these very minimal risks are still discussed in popular discourse, many scientists now agree that genetically modified crops are just as safe to consume and to plant as traditional crops. On a different note, there are possible socioeconomic implications that genetically modified foods can have on developing countries.

Since for-profit companies back genetically modified foods, some fear that their possible market dominance could negatively affect small-scale farmers, particularly poor farmers who cannot compete with large biotech companies for land and a share of the rice market.

Golden rice has the promise to help prevent millions of deaths and alleviate the suffering of children and adults with VAD and micronutrient malnutrition in developing countries.

In addition, allowing its further development may open up more possibilities of enhancing genetically modified, biofortified crops to combat micronutrient malnutrition in developing countries—the main benefit of golden rice. In a debate dominated by anti-GMO activists and Nobel laureates, some views are left in the dark.

Ethical decision-making demands that we consider an issue from a variety of perspectives. Drowning out the voices of those lacking resources impedes our ability to do so. Luckily, with the support of both anti- and pro-GMO activists, voices from developing countries are starting to emerge.

He approved, saying that, like other farmers in countless countries dreaming that their crops may feed their families, communities, and countries with healthy food, golden rice meets his needs.

At the end, he gave his enthusiastic support to the development and expansion of golden rice. Other Philippine farmers, however, gave contrasting reports. Some raised concerns about small farmers becoming indebted to larger corporations for seeds, exploitation of farmers, and human and environmental health.

Their viewpoints are lost in the debate, prompting ethical concerns over who should get to decide what crops to plant in a particular country or region. Stone GD and Glover D. Agric Hum Values. Murnaghan I. Ethical concerns and GM foods. Genetically Modified Foods. May 23, Stone GD and Flachs A. Tickell O. September 8,