June 2002


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GMOs and Gene Flow
Half-Seed PCR
Re-Emerging Biotechnologies: Rehabilitating the Terminator
Genetically Modified Foods
Agbiotech Labeling Bills Introduced
Upcoming Meetings

FAO e-mail conference

Conference 7 of the FAO Electronic Forum on Biotechnology in Food and Agriculture began May 31 and will continue through June 28. The Forum will deal with the issue of gene flow from GM to non-GM agricultural populations (in the animal, crop, fishery and forestry sectors). Anyone may join the Forum and participate in the conference. A Background Document will be provided to Forum Members before the conference. The conference is moderated and all messages posted during the conference will be placed on the Forum website ( For more information, contact To join the Forum (and also register for the conference), send an e-mail to leaving the subject blank and entering only the following two-line text message:

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According to the FAO website, the objectives of the Forum are to allow a wide range of parties, including governmental and non-governmental organizations, policy makers and the general public, to discuss and exchange views and experiences about specific issues concerning biotechnology in food and agriculture for developing countries. The first four conferences dealt with the appropriateness of new biotechnologies in the crop, forestry, animal and fishery sectors respectively for food and agriculture in developing countries. The fifth conference dealt with the implications of agricultural biotechnology for hunger and food security in developing countries, while the sixth was about the impact of intellectual property rights on food and agriculture in developing countries.

Brian R. Shmaefsky

The identification of gene expression products in transgenic plants is necessary for effective screening of transformed lines. Identification can be painstakingly slow in GM plants raised from seeds because of the lag time needed to obtain sufficient tissue for analysis. In many cases, detection requires some differentiation of adult leaf or root tissues in order to get enough sample for quantitative assays. In addition, plant tissue may contain inhibitory products that are difficult to dissociate from DNA and that can hinder PCR amplification. One solution to these shortcomings is to screen transgenic seeds for DNA analysis. Philip Berger, Robert Zemetra, and coworkers of the University of Idaho have recently reported the development of a DNA extraction method from half-seeds that permits rapid PCR screening for transformation and that leaves a viable seed portion available for germination. Their refinements may help researchers to overcome the limitations of time, expense, and space that confound large-scale screening of putative transformants.1

Half-seed extraction is not a new strategy for obtaining DNA from plants, being first reported in 1993 by Chunwongse et al.2 The procedure was developed as a way of extracting DNA from the half seed while leaving the other half available for germination if necessary. Chunwongse's protocol is available on Berger and Zemetra improved on Chunwongse's method by combining half-seed analysis with rapid extraction and characterization techniques. Their DNA extraction method is similar to the technique reported in 1998 by HW Kang et al. 3 of the National Institute of Agricultural Science and Technology in Korea. Kang et al. tagged rapid DNA extraction to rice seed characterization using PCR and RFLP analysis. Their initial analyses were also successful for nine additional species, including the oil seeds, sesame and soybean.

The protocol refined by Berger and Zemetra started with the halving of F1 seeds collected from soft white winter wheat (Triticum aestivum L) transformed with the coat protein gene of wheat streak mosaic virus (WSMV-CP). Seed halves containing the embryo were put aside for later, while the cotyledon portion was used for analysis. The collected endosperm was wrapped in aluminum foil and pulverized. The ground endosperm was mixed into extraction buffer, combined with an equal volume of a 1:1 mixture of phenol:chloroform, and centrifuged. The supernatant was treated with 95% ethanol to precipitate soluble carbohydrates, centrifuged, and the pellet discarded. DNA in the supernatant was then precipitated with 2-propanol and centrifuged to collect the pellet, which was washed with ethyl alcohol and centrifuged a final time. The dried pellet was transferred to buffer for the PCR step. This extraction stage can be done in approximately one hour with prepared reagents.

A commercially synthesized 20-mer primer specific for the WSMVP-CP gene was used for PCR. Standard protocols for a three-step methodology were used for gene amplification. Aliquots were collected after the final cycle and analyzed using 1% agarose gel electrophoresis. A similar protocol was used on the adult leaf tissue of germinated plants. Endosperm and leaf tissue extractions produced similar yields. The authors did note that half-seed extractions provided better PCR resolution than leaf extractions.

In past studies, half-seed germination usually reduced the seed germination percentages and caused seedlings to grow slower that intact seed. Berger and Zemetra found no significant difference in the germination and survivability of half-seeds and whole seeds from the same plants. Some delay in growth and inconsequential morphological changes were noted in plants germinated from half-seeds.

Overall, the technique provides an accurate way for rapidly screening seeds from genetically modified plants. Time and resources are saved by this protocol for three reasons:
1) the time needed for germinating seeds for assay is eliminated;
2) the volume of seed sample needed for analysis is less than that for leaves; and
3) greenhouse or field space is saved, allowing extra room for germinating plants known to have the transgenic gene. The technique should work for any introduced characteristic that can be identified with a specific PCR primer. Culturing cells from seeds positively identified for transformation can improve the high output production of transgenic plants.


1. McCarthy PL, Hansen JL, Zemetra RS and Berger PH. 2002. Rapid identification of transformed wheat using a half-seed PCR assay. BioTechniques 32(3): 560-564.

2. Chunwongse J, Martin GB and Tanksley SD. 1993. Pre-germination genotype screening using PCR amplification of half-seeds. Theoretical and Applied Genetics 86: 694-698.

3. Kang HW, Cho YG, Yoon UH, and Eun MY. 1998. A rapid DNA extraction method for RFLP and PCR analysis from a single dry seed. Plant Molecular Biology Reporter 16: 1-9.

Brian R. Shmaefsky
Dept. of Biology and Environmental Sciences
Kingwood College

Zac Hanley and Kieran Elborough

Four years ago the US Patent Office granted USP#57237651 on `Control Of Plant Gene Expression' to Delta and Pine Land Corporation and the USDA. The concept embodied in this patent and others that followed was later described and derogated as `Terminator Technology'.2 It was presented in numerous forums as evidence that biotechnology is an immoral industry driven by corporate greed. Reaction against Terminator solidified opposition to genetic engineering (GE) among disparate non-governmental organizations (NGOs) and advocacy groups, accelerating the trend towards coalition. This reaction was something of a surprise for many in the modern biotechnology industry, who had thought that Terminator would provide reassuring containment of modified DNA as well as strong protection of their intellectual property. Instead, objectors saw Terminator as a challenge to food sovereignty, particularly in developing nations, and an irresponsible widespread deployment of a potential biological weapon. Now in the new millennium the Terminator may be back, in numerous guises and mandated by governments for sound ecological reasons.

I said I'd be back
Terminator and associated methods are more prosaically known as Genetic Use Restriction Technologies (GURTs). In essence, they impose an expiry date on a genetic enhancement, a built-in obsolescence. Some methods allow controlled deferment of that expiry date, a strategy similar to that used by software companies such as Microsoft supplying fully-featured programs that require activation codes to function beyond a fixed number of uses. In all the extant examples of GURTs, the enhancement is present in a cultivated plant and the control over trait continuation rests with the biotechnology company that developed the cultivar. There are two kinds: variety-restriction GURTs (V-GURTs) render the subsequent generation sterile, while trait-restriction GURTs (T-GURTs) ensure that the enhanced trait is not transmitted to the subsequent generation or that the trait is only maintained in any generation under certain conditions, e.g., on application of a proprietary compound. In practice, farmers purchase elite seeds that provide only one harvest; the seeds from this harvest are sterile, absent, or non-elite and the farmer must buy either seed or trait-maintenance compound from the company.

Objectors to GURTs were able to win support by raising important issues and also by calling on vivid imagery. There are indeed plausible scenarios where some applications of GURTs might threaten developing world economies and ecospheres. Socio-political debate is also won by imagery, and GURTs have been associated in the public mind with Orwellian visions of state control over individual freedoms, government-sponsored sterility programs for `undesirables', the sowing of death in the fields, one more way for the rich to profit from the poor, and the annihilation of bio- and cultural diversity as side effects of the practices of a few economically advantaged countries. This was in addition to the usual accusations against all forms of GE of hubris and arch-reductionism, and prodigious use of the pollution metaphor. As a result, organizations such as the Food and Agriculture Organization (FAO), the Consultative Group on International Agriculture Research, and the Rockefeller Foundation all released public statements condemning GURTs at one time or another. The consensus seemed to be that the consequences of GURT deployment on farmers and consumers in developing nations outweighed the benefits of protecting innovation, and as mechanisms to control unwanted gene spread GURTs were insufficiently perfect. In fact, most of the objections apply only to global use of V-GURTs or global use of those T-GURTs that require trait-maintenance supplements; this distinction is not often pointed out.

However GURTs are now back on the agenda. In July last year a study paper from the FAO (summarized in a recent review3) provided an update on technological progress since the first patent and a balanced appraisal of the projected socio-economic and environmental impacts of the various types of GURT.4 The working group expect there to be a boom in the use of GURTs over the next decade as various technical challenges are overcome, and as governments encourage GURT research seeking technologies permitting GM plant use without `gene escape' to wild relatives or landraces. The UK government's Advisory Committee on Releases into the Environment now describes GURTs as "promising" in this regard. The New Zealand Royal Commission on Genetic Modification recommended that `sterility technologies'(i.e., V-GURTs) receive funding priority from government grants. Patenting activity continues, most recently from DuPont (USP#6297426) and Syngenta (USP#6228643).

Time for a rethink
Why has there been a shift from widespread condemnation to cautious appraisal, even approval? It is because GM crops are here to stay. Acreage planted, species modified, prevalence in individual countries or economic zones, customer preferences—these will change constantly, but GM will never be abolished worldwide. To some this is a nightmare: the release of the `gene genie' is likened to the explosion of the first atomic bomb. Governments and their advisors, the biotechnology industry, and informed consumers are more pragmatic. To them it is time to ensure genetic engineering is subject to appropriate legislative control with due attention being paid to public safety, the environment, national and international agendas, and the pressing problems of the new century. In this context it is time to reconsider technologies such as GURTs. This is not to say that GURTs are to become ubiquitous. There are strong arguments against this, not the least of which is ensuring food security of the many millions who rely on locally bred seeds in developing nations. GURTs have their place only in the portfolio of strategies needed to act responsibly while benefiting from biotechnology.

One objection raised against GURTs is that their use will reduce the routes farmers have to access the best new seeds. It was thought that this might lead to monopolies and inevitably to abuses. Much has changed in the past few years and public education in biotechnology is continuing. With the levels of legislative and public scrutiny, both national and international, that are applied to all GM crops, competition within the biotechnology industry for both profit and acceptance, and the continuing good work of NGOs committed to the needs of farmers over corporations, seed supply monopolies are unlikely to worsen. Moreover, GURTs will be employed first in crops and countries where legislative redress is strongest, markets are diverse and mature, and farmers are rich and future-oriented—e.g., American cotton rather than African cassava.

Detrimental effects of GURTs on agricultural diversity have also been posited but again the arguments are speculative. With all elite germplasm, there is pressure to replace existing local varieties rather than interbreed with them; this is a truism that has no relevancy to GURTs in particular but is often raised. Also, it was proposed that V-GURTs resulting in substandard germplasm might lead to large numbers of weakened plants diluting out local varieties, although the selection pressure for the local varieties and high-quality hybrids would be great. T-GURTs that impose reduced fitness alleviated by trait-maintenance compounds (sometimes labeled `Traitor Technology' and described as making plants "chemically dependent"2) might be particularly damaging to wild relatives and landraces. These scenarios all presume horizontal transfer of genes, and preventative measures are likely to become GM best practise regardless of the use or non-use of GURTs. At the very least, techniques such as the genome-wide dispersal of new genes to render trait transfer vanishingly improbable, or the use of transplastomics, will become prerequisites for approval of GE varieties. GURTs here provide even greater control and precision. Despite the hopes of the early researchers and the nightmares of objectors, GURTs will not change the world; the biotechnology industry learned this in 1998 and now prophets of `genetic holocaust' must learn it again.

GURTs have been vilified and disowned in the past, and a de facto ban on their commercial use resulting from a successful NGO-led campaign has been in place for several years. This is most unfortunate, given the recent furor over the alleged presence of genes from modified maize in Mexican landraces. If GURT research had not been inhibited, would the transgenes in today's elite GE maize be constrained by guaranteed pollen sterility, or be automatically deleted from the genome at the initiation of the reproductive growth phase? Perhaps not given the timeframes available, but if GURTs are finally recognized as valuable tools for the biotechnology industry when used in the appropriate context, they should provide safeguards against similar occurrences.

Reactions to Terminator are a microcosm of the reactions to GE in general. Those opposed wish to ban it outright, thinking nothing good can come of it. A moratorium is a blunt tool, or an inappropriate use of force, and its use here signifies only that a complex issue is being treated simplistically. Rather, each deployment of a GURT (or a GE product) should undergo separate consideration and cost-benefit analysis (one where cost is not measured solely in dollars). The assessment is a scientific one, not a social or political one, and the treatment of GURTs already illustrates where these diverge (e.g., the Indian National Science Academy recognizes that GURTs have uses in controlling gene flow into wild relatives although Indian farmers have uprooted and burnt crops suspected of containing GURTs). In this way, both the industry—dependent on intellectual property protection and keen to be credited with responsible wielding of power—and its customers—anxious for the clear rewards without hidden punishments—can benefit from the ingenuity of researchers who devised tools to protect the interests of both.


1. Search for any US patent mentioned by patent number at

2. See the website of the Action Group on Erosion, Technology and Concentration (formerly Rural Advancement Foundation International) at

3. Visser, Van der Meer, Louwaars, Beekwilder, Eaton (2001) `The Impact of "Terminator" Technology'. Biotechnology and Development Monitor 48: 9-12 (available at

4. Available at

Zac Hanley and Kieran Elborough


Experts View Regimen of Safety Tests as Adequate, but FDA's Evaluation Process Could Be Enhanced

The following is a May 23, 2002, report issued by the United States General Accounting Office to House Representatives John Baldacci and John Tierney of the US House of Representatives.

Proponents and opponents of modern agricultural biotechnology hold passionate views about the benefits and risks of using this technology to produce genetically modified (GM) food. Proponents cite enhanced crop yields, more environmentally friendly food production, and more nutritious foods as reasons to move forward. Opponents of biotechnology argue that not enough is known about the safety of these foods and that they should be more rigorously controlled.

While confidence in the safety of GM foods is essential to their commercial success, governments and consumers from different parts of the world have taken very different positions on their safety and regulation. Some consumers in Western Europe have shown their opposition to this technology by destroying GM food crops, and European regulatory entities have not approved any new GM foods in the past several years. In the United States, consumers and regulatory agencies, such as the Food and Drug Administration (FDA), generally support GM foods, with a number of these foods having been made available for sale in recent years. However, the debate on the safety of these foods is ongoing and may intensify in the future as genetic modifications to foods become increasingly complex.

To ensure public confidence in GM foods, the US biotechnology industry recognized in the early 1990s the need for oversight by FDA, which has primary responsibility for the safety of most of the nation's food supply. In response, FDA published guidelines in 1992 to ensure that companies developing GM foods worked with the agency in assessing the safety of these foods. As part of the process, companies test new GM foods to assess their safety, including their potential health risks, and submit test data to FDA for evaluation. As of April 2002, FDA has evaluated 50 GM foods, many of which have subsequently been placed on the market. Currently, submission of information to FDA is voluntary, but FDA published a proposed rule in January 2001 that would make this submission mandatory.

In light of the continued debate about GM foods, [John Baldacci and John Tierney] asked [GAO] to (1) identify the types of potential human health risks associated with GM foods and experts' views regarding the adequacy of tests used to evaluate these risks, (2) describe FDA's controls for ensuring that companies submit test data it requests and identify experts' views of the agency's overall evaluations of these foods, (3) describe potential changes in future GM foods and any associated changes in tests to evaluate them, and (4) identify experts' views on the necessity and feasibility of monitoring the long-term health risks of these foods.

To conduct this work, we reviewed scientific and technical studies and other literature and spoke with experts in government, academia, private industry, and consumer groups. We selected these experts in consultation with officials from the National Academy of Sciences. As agreed with your offices, we did not assess the potential environmental risks associated with GM food production. In addition, since there have been no GM animals evaluated for commercialization, we did not assess their potential environmental or human health risks. Also, we did not independently evaluate FDA's controls for ensuring it receives safety data. (Further details of the scope and methodology of the review are discussed in appendix I of the full report, accessible at

Results in Brief

GM foods pose the same types of inherent risks to human health as conventional foods: they can contain allergens, toxins, and compounds known as antinutrients, which inhibit the absorption of nutrients. Before marketing a GM food, company scientists evaluate these risks—even though they are not routinely evaluated in conventional foods—to determine if the foods pose any heightened risks.

While some GM foods have contained allergens, toxins, and antinutrients, the levels have been comparable to those foods' conventional counterparts. In evaluating GM foods, scientists perform a regimen of tests. Biotechnology experts whom we contacted agree that this regimen of tests is adequate in assessing the safety of GM foods. While some consumer groups, as well as some scientists from the European Union, have questioned the ethical or cultural appropriateness of genetically modifying foods, experts whom we contacted from these organizations also believe the tests are adequate for assessing the safety of these foods.

While FDA reports that its evaluation process includes the necessary controls for ensuring it obtains the safety data needed to evaluate GM foods, some biotechnology experts state that aspects of its evaluation process could be enhanced. FDA's controls include (1) communicating clearly—through the agency's 1992 policy statement and subsequent guidance—what safety data are necessary for its evaluations of GM food safety; (2) having teams of FDA experts in diverse disciplines evaluate company submissions for GM foods and request additional safety data, if necessary; and (3) tailoring the level of evaluation to match the degree of each submission's novelty, thereby assuring that staff have time to obtain necessary safety data. Nonetheless, FDA's overall evaluation process could be enhanced, according to some experts, by randomly verifying the test data that companies provide and by increasing the transparency of the evaluation process—including communicating more clearly the scientific rationale for the agency's final decision on a GM food safety assessment.

In the future, scientists generally expect that genetic modifications will increasingly change the composition of GM foods to enhance their nutritional value. For example, one company has modified a type of rice to contain beta-carotene. In countries where rice is a dietary staple, this rice may reduce the incidence of blindness caused by vitamin-A deficiency. Current tests have been adequate for evaluating the few GM foods with relatively simple compositional changes that FDA has reviewed so far. New testing technologies are being developed to evaluate the increasingly complex compositional changes expected. Some scientists view these new technologies as a potentially useful supplement for existing tests, while others believe that the technologies will offer a more comprehensive way of assessing the safety of all changes in GM foods.

Monitoring the long-term health risks of GM foods is generally neither necessary nor feasible, according to scientists and regulatory officials we contacted. In their view, such monitoring is unnecessary because there is no scientific evidence, or even a hypothesis, suggesting that long-term harm (such as increased cancer rates) results from these foods.

Furthermore, there is consensus among these scientists and regulatory officials that technical challenges make long-term monitoring infeasible.

Experts cite, for example, the technical inability to track the health effects of GM foods separately from those of their conventional counterparts. A recent report by food and health organizations affiliated with the United Nations also expresses skepticism about the feasibility of identifying longterm health effects from GM foods.

This report contains recommendations to the Deputy Commissioner of Food and Drugs for enhancing the effectiveness of FDA's safety evaluations of GM foods. The recommendations concern the need to randomly verify test data and increase the transparency of the agency's safety evaluations of these foods. In commenting on a draft of this report, FDA agreed with our recommendations and stated that the recommendations would increase the transparency of, and public confidence in, FDA's evaluations of GM foods. FDA also provided technical comments which we incorporated as appropriate.

GAO-02-566 Genetically Modified Foods


On May 22, 2002, in the US House of Representatives, Ohio Representative Kucinich introduced five bills supported by the Campaign to Label Genetically Engineered Food and several cosponsors. The bills, which are sent to a number of relevant committees, are as follows:

H.R. 4812. A bill to provide additional protections for farmers and ranchers that may be harmed economically by genetically engineered seeds, plants, or animals, to ensure fairness for farmers and ranchers in their dealings with biotech companies that sell genetically engineered seeds, plants, or animals, and for other purposes. The bill was sent to the Committee on Agriculture.

H.R. 4813. A bill to amend the Federal Food, Drug, and Cosmetic Act with respect to the safety of genetically engineered foods, and for other purposes. The bill was sent to the Committee on Energy and Commerce.

H.R. 4814. A bill to amend the Federal Food, Drug, and Cosmetic Act, the Federal Meat Inspection Act, and the Poultry Products Inspection Act to require that food that contains a genetically engineered material, or that is produced with a genetically engineered material, be labeled accordingly. The bill was sent to the Committee on Agriculture and to the Committee on Energy and Commerce.

H.R. 4815. A bill to ensure that efforts to address world hunger through the use of genetically engineered animals and crops actually help developing countries and peoples while protecting human health and the environment, and for other purposes. The bill was sent to the Committee on International Relations, and in addition to the Committees on Ways and Means, Financial Services, and Agriculture.

H.R. 4816. A bill to assign liability for injury caused by genetically engineered organisms. The bill was sent to the Committee on the Judiciary and to the Committee on Energy and Commerce.


May 22, 2002 Congressional Record

More meetings can be found at

Pharming the Field: A Look at the Benefits and Risks of Bioengineering Plants to Produce Pharmaceuticals

July 17-18, 2002
The Ronald Reagan Building
The International Trade Center, Washington, D.C.

The PEW Initiative on Food and Biotechnology will host a workshop exploring the potential risks and benefits of bioengineering plants to produce pharmaceuticals. This multidisciplinary conference will present discussion on why biotechnology researchers in industry are looking to genetically engineer plants to make pharmaceuticals; what the advantages of this type of production process could be; what implications these new products could have for the environment and containment strategies; how the regulatory system handles these novel products; and what kinds of future research and information should be made available. Regulatory professionals, researchers, social scientists, public interest groups and industry representatives should all consider attending this two-day conference and workshop. Online registration and additional information about the workshop are available on the Pew website (below).

The workshop is co-hosted by The Pew Initiative (, US Food and Drug Administration, and the Cooperative State Research, Education and Extension Service of the US Department of Agriculture.

Contact: PEW Initiative on Food and Biotechnology
Phone: 202-347-9044

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