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Date:

May 27, 2008

Subject:

GM Corn as 'factory'; GM banana developments; GM citrus; GM eggplant; Monsanto, Syngenta agree

 

* GMO May Help Reduce Brazil's Ag Costs
* Philippines: Corn PSD Update
* Scientists back maize as 'factory'
* Developments in transgenic hill banana
* Syngenta, Monsanto reach technology agreement
* Lawyers seek class-action for biotech rice suit
* New Biotechnology Center coming to FVSU
* Ancient Moss Shares Gene With Flowers
* Polyhydroxybutyrate in switchgrass
* Impacts of Bt eggplant on farmers' wealth, health
* Agrobacterium-mediated transformation of citrus
* Global Warming Petition Project
* Sterile mosquitoes near take-off

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GMO May Be A Solution To Cut Brazil's Ag Costs

- Juliana Hoyl, Cattle Network, May 26, 2008

http://www.cattlenetwork.com/Content.asp?ContentID=224294

SAO PAULO--Climbing fertilizer costs are bringing genetically modified soy and grains into the spotlight in Brazil, according to attendees at a Bunge agribusiness conference in Sao Paulo Monday.

"The effect of fertilizer prices on agricultural costs makes for a very narrow profit margin for farmers. GMOs and new technology could be of great benefit," said Mario Barbosa, chief executive of Bunge Fertilizers, a subsidiary of Bunge Ltd. (BG).

Brazil only permits transgenic soy in its sprawling farmlands. Last year, the country's biosafety council, CTNBio, said it was acceptable to plant transgenic corn from Bayer CropScience Ltd. (506285.BY) and Monsanto Co. (MON).

Farmers won't start planting corn until October, so it remains to be seen if they will plant transgenic corn. Transgenic soy, on the other hand, has become a favorite of farmers looking to squeeze a bit of extra profit per hectare out of their land as overhead costs soar.

According to farm consultancy Celeres, Mato Grosso, the country's leading soy-producing state, is expected to see soy farming costs rise by 41% to 1,584 Brazilian reals ($954.21) per hectare of transgenic soybeans in the upcoming 2008-09 crop. But compared to the BRL1,615-a-hectare cost for traditional soybeans, which require more agrochemical sprays to kill weeds, transgenic soy is the economical winner.

In Parana, the No. 2 soy producer, overhead costs for transgenic soy per hectare are expected to rise to BRL1,398, from BRL1,050 in the 2007-08 crop. Then again, conventional soy costs in the state should hit an average of BRL1,421, up from around BRL1,100 in 2007-08. Author and well-known U.S. futurist, Alvin Toffler, said Brazil will soon join the U.S. in transgenic grain production. "Banning GMO is irresponsible," Toffler said.

Bunge's Barbosa said that with food shortages plaguing many parts of the world, any reluctance to use transgenic soy would cause Brazilian farmers to plant less due to higher costs for conventional soybeans. Demographic increases and a rise in per-capita income have caused food demand to rise worldwide, although supply hasn't accompanied the climb.

Brazil is the world's No. 2 soy producer and has the potential to expand further with strains of crops requiring less fertilizer, producing more yields, drought resistance and other characteristics. Farmers will start buying seeds for the new soy crop in the next few months.

Over half of Brazil's 2007-08 crop was transgenic soy. Given the production costs computed by Celeres Monday, genetically modified soy will, at the very least, remain as popular this season as it was last. Only Monsanto's Roundup Ready soy is commercially approved in Brazil at this time.

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Philippines: Corn PSD Update

- USDA Foreign Agricultural Service, May 23, 2008

http://www.fas.usda.gov/scripts/gd.asp?ID=146294685

Highlight: Enhanced by high corn prices, Philippine corn production will surge in MY07/08 due to better yields and an expanded planted area. Increased food and feed corn consumption will mirror the dramatic production growth during the period. The following year, production growth will likely slow although consumption is expected to continue expanding due to postharvest handling losses. Imports of white corn are predicted in MY08/09 as a result of tight supply entering the year.

View the Acrobat version: http://www.fas.usda.gov/gainfiles/200805/146294685.pdf

View/Download the MS Word version: http://www.fas.usda.gov/gainfiles/200805/146294685.doc

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Guest ed. note: The introduction of Bt corn in the Philippines has made it nearly self-sufficient in this important commodity.

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Scientists back the use of maize as an efficient 'factory' for protein-based pharmaceutical products

- AlphaGalileo, May 23, 2008

http://www.alphagalileo.org/index.cfm?ez_search=1&fuseaction=readrelease&releaseid=529506#resources

Scientists from the Universidad de Lleida (University of Lleida) have published a study confirming that maize seeds are an effective and sure platform within molecular agriculture to alleviate diseases. Over the next few years AIDS could be one of the first diseases to benefit from these results, although regulations for this technology are being developed at the same time as research is being undertaken.

Maize, the third most important cereal in the world, has a great number of advantages for molecular agriculture. Among these are its physiology, its capacity to express recombinant proteins in the seeds, its widespread cultivation and its genetic diversity, as well as being anti-allergenic and non-toxic.

Last March, transgenic maize became the first plant to be developed commercially for medical use. The PNAS review published the following findings: a maize seed with genes from the 2G12 antibody (already known for its capacity to neutralise infection from the virus) could produce antibodies against the transmission of HIV. Researchers from the Departamento de Producción Vegetal y Ciencia Forestal [Department of Plant Production and Forest Science] at the Universidad de Lleida, were those who actually designed this drug during an international project known as Pharma-Planta (made up of 39 European and South African teams), and headed by the British man Paul Christou.

Currently, the same team of scientists from the Universidad de Lleida who took part in this research have put forward in the review Plant Science "a more practical and productive approach to evaluate the ecological and toxicological risks, in which a scientific problem refers to a significant, final evaluation, and the hypotheses of risk predict effects in which the final evaluation is not a transformed plant, but the product resulting from that plant", Paul Christou explains to SINC.

According to the researchers, the use and genetic modification of plants for the production of protein-based drugs is useful for the treatment, prevention and early detection of human and animal diseases, as well as for the production of vaccines against tuberculosis, diabetes and rabies. Paul Christou states that "In the last two decades, plants have been shown to be an excellent alternative for the production of medicines in laboratory research".

Until now, conventional methods using microbial systems and animals have been used in the production of drugs and involve high costs and limits in terms of safety and stability. Amongst other things, excessively high prices prevent the people in most need from accessing pharmaceutical drugs, as the study shows. "Plants offer a solution to the problem because pharmacological production using maize is cheaper", Paul Christou points out to SINC. Paul Christou is also a member of the European Union Expert Committee on Food Safety.

In addition to the price, the proteins produced in maize seeds can remain intact for many years without the need for refrigeration, thus enabling vaccines to be delivered to countries such as those situated in the Tropics and Sub-Saharan Africa.

Risks that plants can present

The risks of the open farming of plants for the production of molecules for pharmaceutical use relate to their impact on the environment through the gene flow, and their impact on the health of animals and humans through inadvertently consuming these. The research team has decided that the regulation processes "should be applied in proportion to the risks of each individual case", as some plants farmed for the production of pharmaceutical drugs are harmless and others vary in their toxicity. In every case a level of risk acceptance has to be established in order to avoid the consequences of any possible exposure.

Paul Christou points out that "the gene flow per se should not be considered "bad" for the environment". He asserts that should this be developed on a commercial basis (anticipated within the next five years), all pharmacological production of maize will be undertaken in specialised locations, "where any risk of gene flow will be unlikely".

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Guest ed. note: See also, "The Outlook for Protein Engineering in Crop Improvement", A. Gururaj Rao, Plant Physiology via RedOrbit, May 27, 2008, http://www.redorbit.com/news/science/1403423/the_outlook_for_protein_engineering_in_crop_improvement/

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TNAU ventures into developing transgenic hill banana

- The Financial Express (India), May 26, 2008

http://www.financialexpress.com/news/TNAU-ventures-into-developing-transgenic-hill-banana/314394/

Tamil Nadu Agriculture University (TNAU) is developing transgenic hill banana, which would be resistant to bunchy top virus (BBTV). Speaking to FE, P Balasubramanian of the TNAU's centre for plant molecular biology said, "We are planning to engineer resistance in the hill banana cultivar, Virupakshi against BBTV. A full-length 850bp replicase gene of BBTV from infected hill banana was isolated in our laboratory.

The isolated sequence showed a high homology to the already reported BBTV replicase gene sequence from India in NCBI database. The isolated replicase gene may be cloned into RNA silencing (RNAi) vector, panda, sourced from Nara Institute of Science and Technology, Japan. The silencing gene construct developed may be used in hill banana transformation." Balasubramanian further said that that in addition to hill banana, TNAU was working on transgenic transformation of the popular Cavendish banana cultivar, Robusta (AAA). So far an efficient regeneration protocol has been standardised on Robusta. Successful regeneration of a diploid banana, Ney poovan (AB) has also become possible. Hill bananas are perennial in nature and are found at an altitude of 2,000 to 5,000 feet above sea level in the region of well distributed annual rainfall of 1,250-1,500 mm. Hill bananas are the ruling crop of the lower Pulneys hill ranges, Sirumalai and Kolli hills of Tamil Nadu from the 1940s. BBTV has been the sole cause for reduction in hill banana cultivation from 18,000 hectare in 1970s to a mere 2,000 hectare at present.

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Guest ed. note: See also, "Introducing a genetically modified banana in Uganda: Social benefits, costs, and consumer perceptions", Enoch Kikulwe, Justus Wesseler, and José Falck-Zepeda, International Food Policy Research Institute, May 2008 (Discussion Paper No. 767), http://www.ifpri.org/pubs/dp/ifpridp00767.asp

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Syngenta and Monsanto reach agreement on corn and soybean technologies

- Syngenta (press release), May 23, 2008

http://www.syngenta.com/en/media/mediareleases/en_080523.html

Syngenta today announced that it has reached a definitive agreement with Monsanto which settles all outstanding litigation relating to the two companies' global corn and soybean businesses.

The agreement gives Syngenta enhanced flexibility in serving its customers and will expand the technology choices available to growers. Terms of the agreement include:

* Monsanto receives a royalty-bearing license to Syngenta's enabling technology for dicamba herbicide tolerance.

* Syngenta receives more favorable marketing conditions relating to its Bt11 trait for European corn borer control.

* Monsanto and Syngenta agree to settle all patent, antitrust and commercial litigation between the companies and their subsidiaries. These disputes include: Syngenta's antitrust action against Monsanto, all infringement cases on herbicide-tolerant and insect-protected corn technologies, and a dispute between the parties on herbicide-tolerant soybean technology.

* Syngenta receives a royalty-bearing license to Monsanto's Roundup Ready 2 Yield™ soybean technology.

* Monsanto and Syngenta agree to cross-enable each other to develop and deliver innovative new herbicide-tolerant and Bt insect-protection products in corn, cotton and soybeans to compete for the business of farmers around the world.

Davor Pisk, Chief Operating Officer of Syngenta Seeds, said: "The need to increase agricultural productivity has never been greater than it is today. We are therefore very pleased to have reached an agreement which expands the choices available across the US corn and soybean markets."

**********************************

Lawyers seek class-action for biotech rice suit

- Christopher Leonard, International Business Times, May 22, 2008

http://www.ibtimes.com/articles/20080522/lawyers-seek-class-action-for-biotech-rice-suit.htm

A federal judge will decide whether to consolidate several lawsuits over genetically engineered rice under one class-action suit that would include thousands of rice farmers throughout the United States.

U.S. District Judge Catherine Perry heard arguments in the case Thursday that hinged on whether farmers suffered economic damage after a strain of Bayer CropScience AG's experimental rice was released into the food supply in 2006.

Some foreign countries temporarily banned U.S. rice exports after the release of the so-called Liberty Link rice, drying up key foreign markets and causing the price for U.S. rice to drop.

Perry made no ruling Thursday, but if she grants the suit class-action status, it could have potentially enormous implications for the biotech seed industry. Every major biotech seed company grows experimental biotech crops outdoors. The U.S. rice farmers say the companies should be held liable for any economic losses on global grain markets if experimental strains escape and crimp export markets.

The Liberty Link strain of rice was not considered harmful to humans, but it wasn't approved for human consumption by the U.S. Department of Agriculture. The department determined the rice likely escaped from a corporate-funded test plot at Louisiana State University, where it was being grown alongside commercial varieties.

Bayer attorney Mark Ferguson said making dozens of lawsuits into a single class-action against his client would be impractical because it would include any rice farmer who set a price for their crop after Liberty Link was released in August 2006.

The price of rice has since skyrocketed, making it hard to determine if those farmers actually suffered a loss from the Liberty Link incident, he said.

"This kind of uncertainty makes the class completely unmanageable," said Ferguson, who is with the Chicago-based firm Bartlit Beck Herman Palenchar & Scott.

Don Downing, an attorney for Gray Ritter and Graham of St. Louis, who represents a group of farmers in the case, said the farmers suffered the same damage because they sell a commodity whose price is set by global markets. Downing said farmers get a price for their rice that is closely tied to those listed by the Chicago Board of Trade. Those prices plunged after the Liberty Link episode was announced.

Downing didn't say what kind of financial damages the farmers would seek. But the sum could be vast, according to testimony from Colin Carter, an agricultural economics professor at the University of California, Davis.

Carter said the rice markets were "shocked" in 2006 when European nations restricted U.S. rice imports. Such a shock becomes a permanent factor in setting the price for a commodity like rice, because traders always know it might happen again.

"If there's a shock, the market remembers that, and it does not dissipate," Carter said. "It's a permanent-type shock."

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New Biotechnology Center coming to FVSU

- Fort Valley State University (press release), May 21, 2008

http://www.fvsu.edu/news/new-biotechnology-center-coming-fvsu

Biotechnology is big business in Georgia, and Fort Valley State University is playing a key role when it comes to this high-tech industry.

The university's College of Agriculture, Home Economics and Allied Programs is scheduled to begin construction this summer on a $3.1 million Agricultural Biotechnology Center that's expected to be completed by Fall of 2009.

To celebrate the 8-000 square-foot facility, local and state politicians, school superintendents, industry leaders and FVSU faculty and staff will gather at a 10:30 a.m. groundbreaking ceremony, May 29, on the Stallworth Agricultural Research Station's lawn on Carver Drive, across from the Wildcat Stadium parking lot.

The facility, funded by the U.S. Department of Agriculture, will have four laboratories and a lecture hall that can accommodate more than 100 people. It will be utilized to expand the already existing research efforts focusing on plant biotechnology, animal biotechnology and applied biotechnology which includes alternative energy.

Training students, who will be mentored by research scientists, will be an important aspect of the center, said Dr. Mark Latimore Jr., the College of Agriculture's interim dean.

"Georgia ranks seventh among states in biotech companies. These corporations employ thousands of people. We are preparing our students for high-paying jobs that require the training and education we provide," Latimore said. "This new, high-tech center is a reminder of the many career options available in the area of agriculture."

Also, by having this center located in rural Middle Georgia, the land-grant institution can continue to advance agricultural teaching and research, and expand its community outreach efforts, Latimore said.

The various types of biotechnology serve many purposes including cutting production costs for farmers, increasing crop yield, improving health and nutrition, and providing new tools for removing environmental toxins.

"We are excited about this center that will further accommodate our research scientists and their efforts to expand research in biotechnology," Latimore said. "Plus, the facility will be used to educate the public which can benefit from possible workshops that address such topics as alternative energy and farming practices."

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Ancient Moss Shares Gene With Flowers

New genetic evidence shows that the same trait developed independently on separate branches of the evolutionary tree

- National Science Foundation, May 22, 2008

http://www.nsf.gov/news/news_summ.jsp?cntn_id=111597&org=NSF&from=news

Biologists have discovered that a fundamental building block in the cells of flowering plants evolved independently, yet almost identically, on a separate branch of the evolutionary tree--in an ancient plant group called lycophytes that originated at least 420 million years ago.

Researchers believe that flowering plants evolved from gymnosperms, the group that includes conifers, ginkgos and related plants. This group split from lycophytes hundreds of millions of years before flowering plants appeared.

The building block, called syringyl lignin, is a critical part of the plants' scaffolding and water-transport systems. It apparently emerged separately in the two plant groups, much like flight arose separately in both bats and birds.

Purdue University researcher Clint Chapple and graduate students Jing-Ke Weng and Jake Stout, along with post-doctoral research associate Xu Li, conducted the study with the support of the National Science Foundation, publishing their findings in the May 20, 2008, Proceedings of the National Academy of Sciences.

"We're excited about this work not only because it may provide another tool with which we can manipulate lignin deposition in plants used for biofuel production, but because it demonstrates that basic research on plants not used in agriculture can provide important fundamental findings that are of practical benefit," said Chapple.

The plant studied--Selaginella moellendorffii, an ornamental plant sold at nurseries as spike moss--came from Purdue colleague Jody Banks. While not a co-author on the paper, Banks helped kick-start the study of the Selaginella genome with NSF support in 2002, and is now scientific coordinator for the plant's genome-sequencing effort conducted by the Department of Energy Joint Genome Institute in Walnut Creek, Calif.

"Because Selaginella is a relict of an ancient vascular plant lineage, its genome sequence will provide the plant community with a resource unlike any other, as it will allow them to discover the genetic underpinnings of the evolutionary innovations that allowed plants to thrive on land, including lignin," said Banks.

Chapple and his colleagues conducted the recent study as part of a broader effort to understand the genetics behind lignin specifically, as the material is an impediment to some biofuel production methods because of its durability and tight integration into plant structures.

"Findings from studies such as this really have implications regarding the potential for designing plants to better make use of cellulose in cell walls," said Gerald Berkowitz, a program director for the Physiological and Structural Systems Cluster at the National Science Foundation and the program officer overseeing Chapple's grant. "Different forms of lignin are present in crop plant cell walls; engineering plants to express specifically syringyl lignin could allow for easier break down of cellulose. Overcoming this obstacle is an important next step for advancing second generation biofuel production."

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Production of polyhydroxybutyrate in switchgrass, a value-added co-product in an important lignocellulosic biomass crop

- Maria N. Somleva, Kristi D. Snell, et. al., Plant Biotechnology Journal, May 21, 2008

http://www.blackwell-synergy.com/doi/abs/10.1111/j.1467-7652.2008.00350.x

Summary

Polyhydroxyalkanoate bio-based plastics made from renewable resources can reduce petroleum consumption and decrease plastic waste disposal issues as they are inherently biodegradable in soil, compost and marine environments. In this paper, the successful engineering of the biomass crop switchgrass (Panicum virgatum L.) for the synthesis of polyhydroxybutyrate (PHB) is reported. Polymer production was monitored in more than 400 primary transformants grown under in vitro and glasshouse conditions. Plants containing up to 3.72% dry weight of PHB in leaf tissues and 1.23% dry weight of PHB in whole tillers were obtained. Results from the analysis of the polymer distribution at the cellular and whole plant levels are presented, and target areas for the improvement of PHB production are highlighted. Polymer accumulation was also analysed in the T1 generation obtained from controlled crosses of transgenic plants. This study presents the first successful expression of a functional multigene pathway in switchgrass, and demonstrates that this high-yielding biomass crop is amenable to the complex metabolic engineering strategies necessary to produce high-value biomaterials with lignocellulose-derived biofuels.

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Potential impacts of Bt eggplant on economic surplus and farmers' health in India

- Vijesh V. Krishna and Matin Qaim, Agricultural Economics, March 2008 (vol. 38(2), pp. 167-180)

http://www.blackwell-synergy.com/doi/abs/10.1111/j.1574-0862.2007.00290.x

Abstract

In this article, the potential impacts of Bt eggplant technology in Indian agriculture are analyzed. Several proprietary Bt hybrids are likely to be commercialized in the near future. Based on field trial data, it is shown that the technology can significantly reduce insecticide applications and increase effective yields. Comprehensive farm-survey data are used to project farm-level effects and future adoption rates. Simulations show that the aggregate economic surplus gains of Bt hybrids could be around US$108 million per year. Consumers will capture a large share of these gains, but farmers and the innovating company will benefit too. As the company has also shared its technology with the public sector, Bt open-pollinated varieties might become available with a certain time lag. This would make the technology more accessible, especially for resource-poor farmers, entailing further improvements in welfare and distribution effects. The wider implications of the private-public technology transfer are discussed. Furthermore, the potential benefits for farmers' health resulting from reduced insecticide applications are examined, using an econometric model and a cost-of-illness approach. These benefits are worth an additional $3-4 million per year, yet they constitute only a small fraction of the technology's environmental and health externalities. More research is needed for comprehensive impact analysis.

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Agrobacterium-mediated transformation of citrus

- Crop Biotech Update, ISAAA, May 23, 2008

http://www.isaaa.org/kc/cropbiotechupdate/online/default.asp?Date=5/23/2008

Genetic transformation has become a very effective tool in improving crops by incorporating genes for better agronomic characteristics, resistance to pests and diseases, and increased nutritional and food quality. This technology can also be advantageously used in improving fruit trees since a specific advantageous trait may be added to a given cultivar or rootstock genome while avoiding burdens of sexual recombination and involvement of deleterious characteristics. Genetic transformation of citrus genotypes has been difficult due to low-efficiencies and presence of non-transformable varieties.

A successful genetic transformation process involves the stable integration of foreign DNA into the host genome and the subsequent regeneration of whole plants from the transformed cells. A research team from Udayana University and Gajah Mada University in Indonesia attempted to genetically transform citrus through Agrobacterium tumefaciens. Internodal stem segments from citrus seedlings were cultured and inoculated with Agrobacterium tumefaciens harboring binary Ti plasmid vector that contained the genes for detectable marker ß-glucuronidase (GUS) and the selectable marker NptII. Results showed that shoots can be regenerated in media with 100 É g/ml kanamycin, and about 10 % of them contain the gusA gene. Some of the GUS+shoots were confirmed by polymerase chain reaction (PCR) analysis.

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Global Warming Petition Project

31,072 American scientists have signed this petition, including 9,021 with PhDs

- Web accessed May 24, 2008

http://www.petitionproject.org/index.html

Purpose of Petition

The purpose of the Petition Project is to demonstrate that the claim of "settled science" and an overwhelming "consensus" in favor of the hypothesis of human-caused global warming and consequent climatological damage is wrong. No such consensus or settled science exists. As indicated by the petition text and signatory list, a very large number of American scientists reject this hypothesis.

Publicists at the United Nations, Mr. Al Gore, and their supporters frequently claim that only a few "skeptics" remain - skeptics who are still unconvinced about the existence of a catastrophic human-caused global warming emergency.

It is evident that 31,072 Americans with university degrees in science - including 9,021 PhDs, are not "a few." Moreover, from the clear and strong petition statement that they have signed, it is evident that these 31,072 American scientists are not "skeptics."

These scientists are instead convinced that the human-caused global warming hypothesis is without scientific validity and that government action on the basis of this hypothesis would unnecessarily and counterproductively damage both human prosperity and the natural environment of the Earth.

Qualifications of Signers

Signatories are approved for inclusion in the Petition Project list if they have obtained formal educational degrees at the level of Bachelor of Science or higher in appropriate scientific fields. The petition has been circulated only in the United States.

The current list of 31,072 petition signers includes 9,021 PhD; 6,961 MS; 2,240 MD and DVM; and 12,850 BS or equivalent academic degrees. Most of the MD and DVM signers also have underlying degrees in basic science.

All of the listed signers have formal educations in fields of specialization that suitably qualify them to evaluate the research data related to the petition statement. Many of the signers currently work in climatological, meteorological, atmospheric, environmental, geophysical, astronomical, and biological fields directly involved in the climate change controversy.

Text of the petition:

We urge the United States government to reject the global warming agreement that was written in Kyoto, Japan in December, 1997, and any other similar proposals. The proposed limits on greenhouse gases would harm the environment, hinder the advance of science and technology, and damage the health and welfare of mankind.

There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gasses is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate. Moreover, there is substantial scientific evidence that increases in atmospheric carbon dioxide produce many beneficial effects upon the natural plant and animal environments of the Earth.

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Sterile mosquitoes near take-off

Malaysia prepares to fight dengue with GM insects.

- David Cyranoski. Nature, May 21, 2008

http://www.nature.com/news/2008/080521/full/453435a.html

Malaysia is looking to battle dengue fever by releasing mosquitoes that have been genetically engineered to be sterile. Although these efforts have stirred public concern, the country's Academy of Sciences is likely to recommend the strategy to the government within a month.

In April, the Institute for Medical Research in Kuala Lumpur indicated that it might release millions of male Aedes aegypti mosquitoes that have been genetically modified to produce offspring that die in the larval stage. The release of enough of the sterile males would theoretically swamp fertile wild-type competitors and crash the population.

This 'sterile insect technique' has been successful in the past, for example in eliminating the medfly from California and the parasitic screw worm from the United States and much of central America. But those insects were sterilized using radiation, which doesn't work as well on mosquitoes. Irradiated mosquitoes are unable to compete with wild-type males to mate with females.

Scientists in Malaysia have been working with mosquitoes created by Oxitec, a company based in Oxford, UK, and founded by University of Oxford geneticist Luke Alphey. Oxitec integrated a genetic element, LA 513, into the DNA of the mosquitoes. This genetic modification kills any offspring in the larval stage if they are not fed the drug tetracycline. In the lab, the mosquitoes are fed tetracycline and grow in the millions. In the wild, the modified gene kicks in, and, in theory, would be able to crash the local A. aegypti population (H. K. Phuc et al. BMC Biol. doi:10.1186/1741-7007-5-11; 2007).

Between September and December of last year, the Institute for Medical Research, part of the Malaysian health ministry, evaluated Oxitec's RIDL-513A strain of A. aegypti in what Alphey describes as "the most realistic environment in which engineered mosquitoes have ever been tested". The engineered mosquitoes did well in competing with wild-type males, mating at the same rate with females. "That would certainly be a step forward over radiation," says Austin Burt of Imperial College London, who works on genetically modifying mosquitoes for malaria control.

Local environmentalists reacted with alarm to media reports last month that the strain would be released on Pulau Ketam, an island fishing village a few dozen kilometres from Kuala Lumpur. The next day, the government issued a press release saying, "Such a release will never be carried out without the proper clearance of the relevant authorities." Researchers from the Institute for Medical Research did not respond to requests for comment.

Gurmit Singh, an environmentalist and chairman of the non-profit Centre for Environment, Technology and Development in Petaling Jaya, says the main problem is that the government never made public details of the long-term potential for ecological disturbance. "How are the mosquitoes produced, and what's the possibility that the mutation could spread?" Singh asks.

Burt notes that people shouldn't be worried because the mosquitoes are designed to die out rather than spread. In his unrelated work, Burt is trying to modify genes to make it difficult for mosquitoes to pass malaria to humans. Unlike Oxitec's mosquitoes, Burt's would need to have a selective advantage for the gene to spread. Burt says that changing the gene pool is "not something you do lightly", but that he hopes to have a mosquito ready for trials in the next five years. Burt's project has, like Alphey's, received money from the Bill & Melinda Gates Foundation, which lists as one of its Grand Challenges for Global Health: "Develop a genetic strategy to deplete or incapacitate a disease-transmitting insect population."

Malaysia's field trials could go ahead long before Burt's. Alphey met with the Malayasian Academy of Sciences on 16 May and says the meeting went well; C. P. Ramachandran, who chairs the relevant committee and has decades of experience in tropical disease research, said "the science is excellent". He adds that, "any risks related to genetically modified organisms must be balanced against the potential benefits," noting that Malaysia has tens of thousands of dengue cases each year.

According to the World Health Organization, spread of dengue since the 1970s has put 2.5 billion people at risk, with an estimated 50 million cases each year.

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*by Andrew Apel, guest editor, andrewapel*at*wildblue.net