1.A food revolution beckons, but few show up
2.GM plants use carbon nanofibres
1.A food revolution beckons, but few show up
By Peter N. Spotts, Staff writer
The Christian Science Monitor, 15 August 2005
It's the kind of breakthrough scientists often dream about.
They have unraveled the complete genetic blueprint for rice - the staple for more than half of the world's population. The development - a key to future genetic blueprints for other cereals and grains - should make it far easier to engineer better, more nutritious crops that could trigger a second "green revolution," whose predecessor - using more traditional farming and breeding approaches - is said to be running out of gas.
There's just one problem. It's not clear the world is ready for another food revolution if it involves splicing foreign genes into crops.
"The initial expectation that this technology would be rapidly adopted turned out to be a bit optimistic," says Michael Rodemeyer, executive director of the Pew Initiative on Food and Biotechnology. "We're in a stall in the development of new GM foods."
To be sure, farmers are producing more bioengineered crops every year. Farmers have found many of these genetically modified crops quite useful. GM soybeans are cheaper to grow; GM papaya has saved Hawaiian growers from a virus that had made their traditional crop unmarketable. But these remain first-generation GM varieties with only indirect consumer benefits.
The next generation - offering consumers better-tasting, more nutritious, or longer-lasting food - is taking longer than the industry's optimists expected, Mr. Rodemeyer adds.
The reasons are legion, analysts say.
Outside the United States, public reluctance and activist campaigns citing everything from environmental concerns to the extensive clout of multinational corporations have slowed the introduction of GM crops. This resistance led Monsanto last year to shelve the first commercially available genetically engineered wheat. US wheat growers worried that GM-wary global customers would buy elsewhere.
Within the US, where farmers plant more than 167 million acres of GM crops, public unease has been less evident. But some analysts expect that to change as companies genetically engineer crops to make them more nutritious or harness crops to produce compounds for drugs.
Second-generation GM crops also pose a tougher scientific challenge than the first-generation did. The traits researchers want to enhance are likely to involve several genes and complex interactions between the plant and its environment.
In this political and scientific environment, rice is poised to become the latest "crop celebre" in the ongoing debate over conventional and genetic-engineering approaches to feeding the world.
The new rice genome, pulled together by researchers worldwide under the umbrella of the International Rice Genome Sequencing Project, was completed three years ahead of schedule. Researchers say much of the credit for the speed goes to Monsanto for making available the rice data it had. Scientists picked rice as the first cereal crop to sequence because of its genome's relative simplicity. Other, more complex cereals share rice's genes, often in the same positions in long DNA assemblies known as chromosomes. Thus, rice has the potential to become a Rosetta stone for reading other key cereal genomes.
"That's one of the exciting aspects" about having the rice genome in hand, says Sally Leong, a research chemist with the US Department of Agriculture's Agricultural Research Service lab in Madison, Wis. And the international nature of the project has helped build capabilities within some key developing countries.
Now comes the tricky part, scientifically associating the genes or gene combinations with specific plant traits and processes. As that information becomes available, traditional breeders can use it to identify useful genes and then trace their movement through several generations. By using seedlings alone, researchers speed up traditional breeding. Rice genetically engineered by inserting foreign genes, however, may face a tougher challenge.
Several charitable foundations and international research institutes are working to enhance the level of "micro- nutrients" - trace minerals such as zinc and iron - as well as vitamin A in rice. The enhanced rice could help in the fight against malnutrition.
Yet golden rice so far has languished, partly because of environmental concerns. Some of the countries that could most benefit have imposed regulatory barriers that are too costly for the public project, says Jorge Mayer, golden-rice project manager at the University of Freiburg, Germany.
In the US, meanwhile, a California biotech company proposing to grow GM rice on a 200-acre plot in Missouri was sent packing in April. The rice had been modified to produce two synthetic human proteins for pharmaceuticals. Anheuser-Busch, worried about contamination of conventional rice, threatened to boycott all Missouri-grown rice used in its brewing activities if the project was approved.
"In the quest to ease global malnutrition, too much emphasis is being placed on genetic engineering without a sufficient look at the risks and alternatives", says Doreen Stabinsky, a geneticist by training who serves as a science adviser to Greenpeace. "We need a realistic assessment of what the technology can and can't do."
2.GM plants use carbon nanofibres
Azonano.com, August 15, 2005
http://www.azonano.com [see alternative url at end]
Researchers are developing new techniques that use nanoparticles for smuggling foreign DNA into cells.
For example, at Oak Ridge National Laboratory, the US Department of Energy lab that played a major role in the production of enriched uranium for the Manhattan Project, researchers have hit upon a nano-technique for injecting DNA into millions of cells at once. Millions of carbon nanofibres are grown sticking out of a silicon chip with strands of synthetic DNA attached to the nanofibres. Living cells are then thrown against and pierced by the fibres, injecting the DNA into the cells in the process.
Its like throwing a bunch of baseballs against a bed of nails...We literally throw the cells onto the fibers, and then smash the cells into the chip to further poke the fibers into the cell. - Timothy McKnight, engineer, Oak Ridge Laboratory
Once injected, the synthetic DNA expresses new proteins and new traits. Oak Ridge has entered into collaboration with the Institute of Paper Science and Technology in a project aimed to use this technique for genetic manipulation of loblolly pine, the primary source of pulpwood for the paper industry in the USA.
Unlike existing genetic engineering methods, the technique developed by Oak Ridge scientists does not pass modified traits on to further generations because, in theory, the DNA remains attached to the carbon nanofibre, unable to integrate into the plants own genome. The implication is that it would be possible to reprogram cells for one time only. According to Oak Ridge scientists, this relieves concerns about gene flow associated with genetically modified plants, where genes are transferred between unrelated organisms or are removed or rearranged within a species.
If the new technique enables researchers to selectively switch on or off a key trait such as fertility, will seed corporations use the tiny terminators to prevent farmers from saving and re-using harvested seed - compelling them to return to the commercial seed market every year to obtain the activated genetic trait they need?
This approach also raises a number of safety questions: what if the nanofibres were ingested by wildlife or humans as food? What are the ecological impacts if the nanofibres enter the cells of other organisms and cause them to express new proteins? Where will the nanofibres go when the plant decomposes in the soil?
Carbon nanofibres have been compared to asbestos fibres because they have similar shapes. Initial toxicity studies on some carbon nanofibres have demonstrated inflammation of cells. A study by NASA found inflammation in the lungs to be more severe than in cases of silicosis, though Nobel laureate Richard Smalley, Chairman of Carbon Nanotechnologies Inc. gives little weight to these concerns: We are confident there will prove out to be no health hazards but this [toxicology] work continues.
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