New Variety of Golden Rice has Increased Levels of Healthful Betacarotene
Date: 2.2.2006
Researchers pledge to donate improved seeds to developing world farmers.
Researchers in the United Kingdom have developed a new variety of genetically enhanced rice that has more than 20 times the level of betacarotene — which the human body can transform into healthful vitamin A — found in an earlier variety. And that could help alleviate a variety of diseases, including blindness, in the developing world.
In a peer-reviewed article in Nature Biotechnology, researchers from the biotech company Syngenta said the second generation of golden rice they developed has 23 times more betacarotene than the first generation developed five years ago.
"This new development is further evidence that golden rice could complement existing efforts that seek to end blindness and other diseases caused by vitamin A deficiency," said a statement from the Golden Rice Humanitarian Board, which oversees the development of the enhanced rice. "Golden rice is but one tool in a larger toolbox from which country health officials, farmers and consumers could choose in their efforts to fight vitamin A deficiency."
Instead of inserting a gene from daffodils into the rice, as had been done with the first golden rice variety, the researchers borrowed a similar gene from corn and added it to the rice.
"We found it made a dramatic difference," Rachel Drake, head of Syngenta's research team in the U.K. that developed the new rice, told New Scientist magazine. "I'm absolutely delighted, and I think it's a very compelling story."
Vitamin A deficiency is responsible for up to 500,000 cases of childhood blindness — and between 2 and 3 million deaths — each year and also is a contributing factor in causing other infectious diseases, according to the World Health Organization.
It's estimated that up to 40 percent of children in the developing world under the age of five suffer from immune system weaknesses associated with a deficiency of vitamin A, with most of the problems concentrated in Southeast Asia and Africa.
Syngenta has agreed to donate seeds and research from the second generation of golden rice to the Golden Rice Humanitarian Board so they can be distributed — once the necessary government approvals are obtained — to farmers around the world.
The new golden rice may well help silence biotech critics, who have claimed that the first generation of golden rice did not contain enough betacarotene to make a significant impact on vitamin A deficiency.
Whereas the first generation of golden rice had just 1.6 micrograms of golden rice per gram of rice, the improved variety has 37 micrograms per gram of rice. Researchers say there is enough betacarotene in a single 72 gram serving of rice — slightly more than the typical child's serving of 60 grams — to prevent night blindness and vitamin A deficiency in children.
And since rice is frequently eaten several times a day in Asia, the newer strain of golden rice could deliver even more vitamin A.
Before the second generation of golden rice is commercially produced, it must first be approved by the countries where it is to be planted, which could take several more years.
The Golden Rice Humanitarian Board has expressed frustration with the slowness of the approval process given that between 2 and 3 million children die each year from illnesses linked to vitamin A deficiency.
"While the Humanitarian Board understands that every new transgenic event must comply with regulations to guarantee the safety of the product, it has a hard time dealing with nonscientific arguments that unnecessarily delay the adoption of the technology vis-avis the human tragedy brought about by vitamin A deficiency," the board's Web site said.
The board is led by Ingo Potrykus, professor emeritus of the Swiss Federal Institute of Technology in Zurich, Switzerland, and Prof. Peter Beyer of the University of Freiburg in Germany, who headed the research team that developed the first version of golden rice. It also includes representatives from the International Rice Research Institute, the philanthropic Rockefeller Foundation, USAID, universities and other organizations.
The board also noted that golden rice has been in development since 1980 and that "reputed ecologists, including opponents of the technology, have so far concluded that golden rice poses no imaginable risk to the environment." It suggested that opposition to biotechnology is based more on politics than sound science.
Since the first generation of golden rice was unveiled in 1999-2000, however, several promising developments may help to move the approval process forward:
Developing world farmers have embraced biotechnology. An estimated 8.25 million farmers in 17 countries now plant biotech crops, according to the International Service for the Acquisition of Agri-biotech Applications. 2004 marked the ninth straight year that the planting of biotech crops increased by double-digit levels.
In 2002 the Philippines became the first country in Asia to approve the commercial planting of a biotech food crop — corn — for human consumption. (Several Asian countries already permit the planting of biotech cotton.)
China and several other Asian countries are moving closer to approving different varieties of biotech rice for planting.
The Golden Rice Humanitarian Board said that while the new rice is an exciting advance, it does not offer the sole solution to malnutrition in developing countries.
"Malnutrition is rooted in political, economic and cultural issues that cannot be magically resolved by a single agricultural technology," the board said. "Golden rice offers developing countries another choice in the broader campaign against malnutrition."
"Soure":[ http://www.whybiotech.com/index.asp?id=4983]
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