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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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Suggested Citation:"1. Introduction." National Research Council. 2004. Biological Confinement of Genetically Engineered Organisms. Washington, DC: The National Academies Press. doi: 10.17226/10880.
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1 Introduction WHAT ARE GENETICALLY ENGINEERED ORGANISMS? The human community has engaged in genetic modification for thou- sands of years with the domestication and subsequent breeding of microbes, plants, and animals for use in agriculture, medicine, and industry. The developments of the past 25 years, which involve the insertion and manipu- lation of genes within an organism's DNA, however, constitute a significant advance from the process of selective breeding. Four major parameter shifts from selective breeding to genetic engineering illustrate both the power of the new methods and the controversy that surrounds their application (Kreuzer and Massey, 2001). First, selective breeding operates on the whole organism, so factors, such as generation time and development patterns, determine the speed with which a trait or characteristic is selected. Second, selective breeding is less precise, inevitably moving sets of genes that are linked to those targeted for introgression. Many of those linked genes have unknown functions. Third, the certainty surrounding genetic expression is low for selective breeding; genetic change is often poorly characterized. Finally, the genes and traits that can be used for genetic improvement typically come only from the same species or from one that is closely related (Kreuzer and Massey, 2001). In contrast, genetic engineering operates at the cellular or molecular level so it is possible to select and transfer single genes. The genes of interest generally are well characterized, and they can come from other species, including those from distant taxa. Several definitions of genetically engineered organism (GEO) have 14

INTRODUCTION 15 emerged over the past few years from an assortment of institutions and policymakers, but there appears to be a general understanding that a GEO is "an organism that has been modified by the application of recombinant DNA technology" (FAO, 2002). Although GEO and GMO (genetically modified organism) often are considered interchangeable terms, this report uses GEO to be consistent with recent reports of the National Research Council (NRC, 2002a; 2002b). WHAT IS BIOCONFINEMENT? Since the first release of GEOs into the environment in the mid-1980s, public and scientific concern has focused on the potential consequences of the escape of those organisms and their associated transgenes into natural and managed ecosystems. It has long been asserted that GEOs could not compete successfully with wild populations, and therefore that they could not survive in the wild over the long term. Recent and longer standing ecological studies might suggest otherwise, however--especially if GEOs can cross with wild relatives (Linder et al., 1998; Snow et al., 2003). As a result, there is interest in developing methods to confine some GEOs and their transgenes to designated release settings. There also are cases in which the movement of transgenes from one domesticated plant or animal variety to others must be confined. Many confinement methods are biological, and they are referred to as bioconfinement in this report. Bioconfinement of GEOs is in the conceptual and experimental stages, although some methods have been applied to control nonengineered organ- isms. Bioconfinement includes the use of biological barriers, such as induced sterilization, that prevent GEOs or transgenes from surviving or reproducing in the natural environment (Chapter 3). More specifically, sterility has been induced in some species of salmon and oysters through manipulation of the number of chromosomes in individual animals (Chapter 4). It also is possible to introduce a single genotype of a self-incompatible plant to prevent seed formation. This practice is used in horticulture and agriculture (Chapter 3). There is a long list of potential techniques and principles for the bio- confinement of GEOs (Chapters 3, 4, and 5). How important they become will depend on many factors, as this report outlines. The Committee on Biological Confinement of Genetically Engineered Organisms notes that this report has been prepared in the early days of those emerging tech- niques. Over the course of preparing this report, the committee informally surveyed several representatives from the private sector about emerging bioconfinement methods. While not a comprehensive survey, the commit- tee came away with the impression that, at this time, industry research efforts on new bioconfinement methods were fairly modest and that current efforts mainly focused on utilizing and refining existing well-established

16 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS methods of confinement (such as physical, spatial, and temporal isolation) with GEOs under development. The bioconfinement principles and methods discussed here are likely to be improved and augmented through research and development over the years to come. OTHER CONFINEMENT METHODS It is useful to consider different confinement measures because every type has an inherent vulnerability to failure. The two other broad types of confinement measures, the physical and physicochemical barriers, prevent the escape of organisms or their genetic material (via gene flow to relatives) from the production system into accessible ecosystems. A brief introduction appears below, and a more detailed discussion of issues to consider in applying those barriers to the confinement of genetically engineered organ- isms appears in a document by the Scientists' Working Group on Biosafety (1998). Physical barriers are devices, such as screens, that prevent organisms at a given life stage (gamete, asexual propagule, juvenile, adult) from leaving the production operation or facility. For annual crops and for insects, physicochemical barriers include screens with appropriate mesh sizes on windows and other openings of greenhouses. Another effective barrier for confinement of plants and insects is the use of negative air pressure achieved when the volume of air exiting a space or chamber exceeds the air intake volume to contain pollen, spores, or mobile insects (Traynor et al., 2001). Physical barriers for fish, shellfish, and algae produced in aquaculture systems include screens in pipes and channels of water that flow in and out of ponds or tanks, effluent drain structures with multiple mechanical barriers (French drains), and the fine sand filters that often make up one component of closed-loop aquaculture systems. It is particularly important to match the design and operation of a mechanical barrier to the smallest life stage it is expected to restrain, keeping in mind that gametes or asexual propagules of aquatic organisms can be miniscule (viable eggs and newly fertilized embryos with diameters less than 10 micrometers). Schematic diagrams of physicochemical barriers--along with examples of operating criteria designed to hold back specific life stages--appear in two scientific biosafety guides (Agricultural Biotechnology Research Advisory Committee, 1995; Scientists' Working Group on Biosafety, 1998). Physicochemical barriers induce mortality through lethal physical alterations to the escape routes to the environment immediately external to the site of GEO production with the aim of achieving 100% mortality. Physical barriers applied in the production of genetically engineered fish, shellfish, and algae include the use of temperature changes, changes in pH, or the addition of dissolved chlorine to water that flows out of fish tanks or

INTRODUCTION 17 ponds before the effluent is discharged into the environment. Typically, the effluent water passes through a chamber that imposes the lethal condition for a given contact period and then, before the effluent is discharged to a natural water body, the effluent water is restored to ambient environmental conditions to maintain the water quality of the receiving water. It is fairly easy to impose lethal physical conditions because most farmed aquatic species have a well-known and narrow range of physical parameters needed for survival. The mechanisms for altering these are well understood from many years of industrial and municipal water treatment. Water tempera- ture changes are easily achieved by heating and cooling and pH can be adjusted using acids and bases. Chlorine, even at low levels (one part per million), is lethal to most organisms. Bioconfinement Redundancy In many technology applications, the principle of "redundancy" guides efforts to reduce the probability that predictable hazards will occur, and thus achieve the benefits of technology. Generally, two or more safety measures are applied to product design and use, each with fundamentally different strengths and vulnerabilities, so that the failure of one will be balanced by the integrity of another. A unique feature of biotechnology that distinguishes it from other recent technologies is the fact that it involves living organisms and products. As such, biotechnology, like all biological systems, inherently operates with a given level of uncertainty. This attribute makes the application of the principle of redundancy particularly relevant to bioconfinement as well. In many cases, redundancy will involve the application of an appropriate mix of biological, physicochemical, and mechanical confinement (Agricultural Biotechnology Research Advisory Committee, 1995; Kapuscinski 2001; Scientists' Working Group on Bio- safety, 1998). In other cases, it may be possible to combine two barriers of the same type but whose failures would be independent events, such that a failure of one barrier does not trigger a failure of the other. One application of the principle of redundancy in aquaculture of genetically engineered (GE) fish combines physicochemical barriers (float- ing cages that are highly prone to failure and land-based, flow-through units that are less prone to failure) with biological confinement consisting of production of an all-female line of sterile fish. SCOPE OF THE REPORT This report reviews biological methods used to confine genetically engi- neered organisms. It focuses on the genetic mechanisms of bioconfinement,

18 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS such as induced sterility, but it also identifies and discusses other available or possible methods. The following specific questions are addressed: · What is the status of scientific understanding about various biologi- cal confinement methods for genetically engineered organisms? · What methods are available, and how feasible, effective and costly are these methods? (e.g., How well would these methods fit with existing practices for research and agricultural production? When and for what systems are the individual methods appropriate?) · What do we know about when and why methods fail, and what can be done to mitigate those failures? · When these methods are used in large-scale applications, what proce- dures can be used to detect and cull individuals for which the biological confinement methods have failed? What is the cost-effectiveness of these mitigation, detection, and culling procedures? · What are the probable ecological consequences of large-scale use of biological confinement methods (e.g., deployment of sterile organisms) on wild populations, biological communities, and landscapes? · What new data and knowledge are required for addressing any of these important questions? Although not a specific focus of the report, the social acceptability of bioconfinement methods is discussed in the introduction and as context for the technical analyses. This report examines a variety of issues associated with bioconfinement of transgenic fish and shellfish, trees and grasses, insects, and microbes. Fish, such as transgenic farmed salmon, could pose special environmental risks because of the inadequacy of physical confinement methods (net pen enclosures) and because of the potential for escapees to interact with and harm wild fish stocks--many of which already are in decline. There is concern about the gene flow of trees and grasses related to their high pollen production and the presence of sexually compatible wild species. Those plants are perennials, and environmental exposure issues could differ from those associated with corn, soybean, or other annuals. Concerns regarding perennials are bolstered by the longevity of individual plants and by charac- teristics that inhibit growth of other species, including--in the case of trees-- their large, shade-producing physical structures and the accumulation of surface litter they cause. There have been field tests of transgenic insects and animals, and more are under consideration, but several genetically engineered crops are now in relatively common use. Algae, plants, mammals, insects, shellfish, and microbes are being genetically engineered in the laboratory and are now or could someday be considered for release into the environment. Although

INTRODUCTION 19 each species will have unique characteristics that determine the effectiveness of the bioconfinement methods applied, there are some general principles that could be applied to a common framework for safe use. INTERNATIONAL ASPECTS Although much of the discussion of confinement of GEOs occurs in a domestic context, several significant international dimensions are of interest. Development, production, and use of GEOs is on the rise in other nations-- including Argentina, Brazil, China, Canada, Cuba, and India--in part because of the global character of the biotechnology business, which can transport research, field testing, and production from the United States to other nations as it becomes expedient to do so. Business enterprises could choose between regulatory or intellectual property regimes, for example, and move GEOs with confinement techniques from an environment in which they are suited to one in which they are not. Similarly, individual people or businesses desiring to use a GEO could import or export that organism for their own purposes. GEOs can be moved between countries by any number of means--international trade, travel, tourism, transport, and aid, for example--as well as unintentionally in ocean and river cur- rents, wind, storms, and floods. Animals such as birds, insects, and rodents could be vectors, and the organisms themselves can move across borders. As a matter of United States public policy, addressing bioconfinement thus requires that the issues of efficacy, public concern, and environmental consequences be considered as they pertain here and abroad. Similarly, the United States has an interest in bioconfinement policy--and practice--in countries from which GEOs could come and in the effectiveness of inter- national regulation of such movement. No one nation can control all of the confinement issues that could affect its environment, in part because of the dispersal of GEOs across national boundaries. The committee's finding is that adequately addressing bioconfinement may require international cooperation. HISTORY OF CONFINEMENT The history of genetic engineering is coextensive with the history of confinement and containment methods. The first recombinant DNA mol- ecule was engineered by researchers led by Paul Berg at Stanford in 1972. They isolated and employed a restriction enzyme to cut DNA from two different viruses­­the bacterial virus, lambda, and the mammalian virus, SV40­­and used the enzyme ligase to paste two DNA strands together to form a hybrid circular molecule. The goal was to use the hybrid virus as a vector to deliver genes to bacteria. In a short period of time, several recom-

20 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS binant DNA (rDNA) organisms were created and vectors were developed. The research raised fears about the danger posed by the new organisms. Berg suspended the work in 1972 in response to charges that the risks to laboratory workers and to the general public were unknown and poten- tially grave (Wade, 1979; Wright, 1994). The use of Escherichia coli (E. coli) as a model organism exacerbated those concerns. The scientific community was divided on the potential dangers of research with GEOs, and there was no accord on the appropriate steps to take. Several committees were formed in the United States and in other countries, including one convened by the National Academy of Sciences (NAS) (Wright, 1994; for the letter to NAS that instigated NAS action, see Singer and Soll, 1973). At the same time, activists and nongovernmental organizations (NGOs) began a campaign of opposition that called on the government to regulate, control, and limit the action of scientists in this area. Most of the scientific community saw tremendous potential in genetic engineering, both for basic science and the practical developments to which it would lead, including therapeutic biological agents like human insulin, genetically engineered crops and animals, and methods of gene therapy. In response to concerns about the hazards of the research, a moratorium was imposed (with strong support from the National Institutes of Health [NIH]) on some experiments. In 1975, an international meeting in Asilomar, Cali- fornia led to consensus on the importance of developing safety measures for use in the genetic engineering of bacteria and viruses (Wade, 1979; Wright, 1994). The primary concerns at the time involved the possibility that genetically engineered bacteria could develop drug resistance or have other traits harmful to humans. There was concern that the accidental release of altered bacteria could have disastrous effects on public health. There was additional worry that as a result of their modification, harmful viruses could extend their host range to humans. "Biological containment" was one of the first mechanisms proposed to control the risks of the new technology. Among the first groups to address the risks of recombinant DNA research in Great Britain was the Ashby Committee, which was organized by the Advisory Board for the Research Councils. In written testimony to that committee, Sydney Brenner of the Cambridge Laboratory for Molecular Biology warned of the dangers of having potentially dangerous materials handled by improperly trained sci- entists. In 1974 he proposed creating bacteria that were genetically engi- neered not to survive outside of the laboratory, to reduce the possibility of those organisms transferring their DNA to other organisms. The suggestion was endorsed in the Ashby Committee report. This was the first time the concept of biological confinement was introduced in an official report (Wright, 1994). The attempts at self-regulation by the scientific community culminated

INTRODUCTION 21 in the 1975 Asilomar meeting and in the creation of the NIH Recombinant DNA Advisory Committee (RAC). Soon after the Asilomar meeting, the first RAC meeting took place to construct systematic safety guidelines. Agreement proved difficult, and it took 16 months (until June 1976) for consensus on safety protocols for assessing the degree to which a particular genetically engineered organism represented a hazard and then applying two independent confinement systems--one physical, the other biological. The physical confinement systems were defined in terms of standard tech- niques of microbiology research that were in common use in U.S. laborato- ries. Laboratories were identified on a four-point scale: from BL1-BL4. BL1 facilities were standard microbiology laboratories that used no special safety procedures. A BL2 rating represented little more. Aerosols were to be con- fined to cabinets and eating and drinking were prohibited. A BL3 rating required the use of special procedures, equipment, and design at an esti- mated cost in 1977 of $50,000 for a typical facility (Wade, 1979). Included in the BL3 designation were cabinets which controlled of air flow out of, but not into the laboratory. BL4 laboratories were those in which extremely pathogenic agents, such as smallpox or Lassa fever virus, were studied. Costing about $200,000, a BL4 laboratory was less expensive to build from the ground up than to create through modification of an existing facility. In addition to requiring physical confinement, the RAC protocols listed the first systematic assessment of biological confinement, graded on a scale from EK1 to EK3. For EK1, researchers would use the standard strain of E. coli (K12) as a host. That strain is not very robust after multiple genera- tions of laboratory rearing. The only vectors authorized for use in EK1 were plasmids that had a low probability of transferring DNA to other bacteria. The suggestion of the Ashby Committee was taken up for EK2 conditions. In an EK2 laboratory, the genetically engineered organism and the vectors would be versions of the handicapped bacteria further engi- neered to have only a 1 in 100 million chance of survival outside the laboratory, according to laboratory tests. For example, researchers devel- oped a strain of E. coli that could survive only in the laboratory because its survival depended on specific chemicals that do not occur commonly else- where (Curtiss, 1978, see Box 5-1). EK3 laboratories required genetically engineered hosts for which the laboratory findings of EK2 organisms had been confirmed through actual feeding to animals, humans, or both. The system of safeguards came under criticism both from within and outside of the scientific community. Several prominent scientists, and many nonscientists, charged that the entire discussion and protection system focused far too narrowly on health risks, and that it failed to address broader ethical and evolutionary issues. Many scientists pointed out that the physical confinement system depended too much on the behavior of the people working in laboratories.

22 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS Battles over the guidelines and whether legislation would be needed-- particularly with regard to non-NIH-funded recombinant DNA research in the private sector continued for several years. As a result the RAC evolved to include members of the general public. Eventually, the increase in data on the safety of handicapped genetically engineered model organisms and the growing recognition of the benefits of the emerging technology, both commercial and therapeutic, quieted the debate. Many of the requirements for bioconfinement were relaxed, and research was allowed to proceed. The guidelines were broadened to include any institution receiving NIH funding (regardless of the source of funds for a given experiment) and some com- mercial laboratories, which were subject to limits imposed by consider- ations of liability (Uchtmann, 2002). The philosophy during this period relied more on establishing professional norms and voluntary compliance than on extensive government regulation as the basis of protecting the public (Uchtmann, 2002; Wright, 1994). In the 1980s, GEOs moved from the laboratory to the field, requiring a major shift in confinement strategy. The NIH guidelines initially prohibited "deliberate release." The first attempt to obtain RAC approval for a field trial involved "ice-minus" bacteria. Researchers at the University of Cali- fornia, Berkeley, had created a strain of Pseudomonas syringae that could reduce frost formation on plants where it replaced naturally occurring populations of bacteria (Sprang and Lindow, 1981). The first request for field trials in 1982 was postponed, but approval came in 1983. Activists filed a lawsuit and successfully halted the trials. Once more, genetic engi- neering produced a rancorous debate. The media, the courts, and the scien- tific community voiced their opinions about the risks and benefits of general release of GEOs into the environment and about how the regulation and local laws should work (Uchtmann and Nelson, 2000). The legal maneuverings and political debates delayed field trials for another four years. By 1988, although the trials showed that the bacterium could reduce ice formation, plans to commercialize the product were abandoned. Clearly, a coordinated regulatory system was needed for field testing GEOs. The 1984 National Environmental Policy Act (NEPA) required envi- ronmental assessment of the impact of any action taken by RAC--and hence by NIH--that might affect the environment. By 1986, a coordinated framework, built on existing laws and institutions, had been developed to satisfy NEPA (51 Fed Reg 23302 June 26, 1986 described further in Chap- ter 2). Henceforth, regulation would focus on the products of genetic engi- neering rather than on the process. The degree of confinement necessary for approval under NEPA would depend on the traits that were to be intro- duced into an organism and on the results of an environmental assessment. For many types of crop plants, such as herbicide-tolerant soybean, no confinement would be required by US regulatory agencies.

INTRODUCTION 23 By the early 1990s, researchers were developing some of the biological confinement methods described later in this report. The difficulty of relying on physicochemical confinement methods for fish, in particular, led to the development of new methods, including sterile triploidy, antifertility genes, and "suicide genes" (Aleström et al., 1992; Donaldson et al., 1993). Inter- national discussion about transgenic organisms and the confinement methods that would be required to ensure the environmental safety and health of various populations proceeded along the lines of the initial Asilomar-based framework. In Oslo, Norway, the First International Symposium on Sustain- able Fish Farming similarly led to discussion of the need for international agreement on the use of bioconfinement to supplement physical barriers (Aleström, 1995). An important development in the technology of bioconfinement was the invention in the late 1990s of the Technology Protection System (Chap- ters 3 and 6) by Melvin Oliver--a U.S. Department of Agriculture (USDA) researcher­­who created it in conjunction with Delta and Pine Land Com- pany. Its purpose was to protect the intellectual property rights of bio- technology companies that develop seeds for crops. In partnership with Monsanto, the Delta and Pine Land Company was working to develop a strain of cotton that, with the application of the Technology Protection System (TPS), would not produce usable seed at the end of each growing season. The companies saw the potential to apply the technology to a variety of genetically engineered products, making it a potentially valuable commodity in itself. Delta and Pine Land (and later Monsanto) anticipated potential use of the technology even for corn. As genetically engineered food crops came into common use in the United States throughout the 1990s, with no stipulations about confine- ment, several new concerns emerged about cases for which confinement would be desirable. First, there was concern that those crops would intro- duce transgenes into plant and animal populations for which there was a strong social, ethical, or economic interest in maintaining non-GEOs. For example, farmers of organic products were worried that pollination from genetically engineered plants would introduce transgenes into their crops and threaten their ability to sell their harvest as certifiably organic. Reports that transgenes were found in indigenous landraces of maize in Mexico (Alvarez Morales, 2002; Quist and Chapela, 2001) fueled several conflict- ing controversies (e.g., Christou, 2002; Martinez-Soriano et al., 2002; Metz and Fütterer, 2002; Kaplinsky et al., 2002; Quist and Chapela, 2002), including the question of how deregulation of a crop in the United States is viewed by other nations. The possibility that crop genes or crop products not approved for human consumption could enter the food supply brought attention to other problems with existing confinement methods, such as spatially separated

24 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS fields. The difficulty of segregating commodity crops was made apparent in the case of StarLink corn (see Box 2-1). StarLink produces the Bacillus thuringiensis toxin protein Cry9c. In 1998, the United States Environmental Protection Agency (US EPA) approved StarLink corn for animal consump- tion and for industrial production of ethanol. Human consumption was not approved because Cry9c resists both heat and digestion, and those traits are associated with allergens. Thus, US EPA determined that the protein was itself a potential allergen. In September 2000, several newspapers reported that StarLink corn had been detected in Taco Bell brand taco shells sold in grocery stores. The Genetically Engineered Food Alert, a coalition of envi- ronmental groups, had sent the shells to the Iowa-based company Genetic ID for testing. That independent laboratory reported that the sample taco shells contained at least 1% StarLink corn. Kraft Foods, which distributed the taco shells, responded the next day with a press conference and a "special report" posted on its web site. Kraft stated that it was conducting its own tests to confirm the results, and would voluntarily recall the taco shells if Cry9C was detected. Kraft later confirmed that Cry9C was in the taco shells, and it recalled the nearly 3 million boxes. Subsequently, hundreds of corn-based products were recalled because of concern about StarLink contamination. In late September 2000, Aventis--the company that developed and produced the seed--suspended sales. That was the first time a biotechnology company had frozen sales of a genetically engineered seed. By agreement with USDA, Aventis bought back all the remaining StarLink corn to ensure that it would be used only for animal feed and ethanol production (at a cost of roughly $100 million). There is no evidence that StarLink produced an allergic reaction in any person. Newer applications of GEOs include plant-made pharmaceuticals (PMPs) and crops that are used in production of industrial compounds. Given the large start-up costs of factories that produce biologics, such as human monoclonal antibodies, PMPs represent a potentially lucrative market. But the developments also heighten worries about the escape of transgenes or transgenic plant products into the food supply. Among the first companies to come to public attention was Prodigene, a leader in PMP development. In 2001, Prodigene planted corn genetically engineered to produce pharma- ceutical products at various field sites. The next year, at one of the Nebraska sites, a conventional crop--soybeans--was grown on the land that had been used for the experimental crop. Seed from the experimental crop germinated among the soybean plants. Although volunteer corn initially went undetected, eventually, inspectors from the USDA Animal and Plant Health Inspection Service identified the plants. Nonetheless, the plants were subsequently harvested with the soybeans. Pieces of transgenic corn plants ended up with the soybeans in a grain elevator. USDA imposed a quaran-

INTRODUCTION 25 tine of 500,000 bushels of soy. Some commentators hold that this demon- strates success of the current regulatory system; others argue that it shows that companies cannot be trusted to apply adequate protection. In either case, the importance of confinement methods has been demonstrated as have their potential weaknesses (Taylor and Tick, 2003). SOCIAL ACCEPTABILITY OF BIOCONFINEMENT METHODS While the need for effective confinement methods for some types of GEOs has become more apparent in recent years, the majority of the bioconfinement methods discussed in this report are in development and have not been used in conjunction with commercially available GEOs. Based on the committee's best judgment and collective expertise, it appears that the public has had little opportunity to develop opinions regarding this facet of biotechnology. It is likely that the public's acceptance of GEOs and bioconfinement will be closely linked or correlated, and that some GEOs could receive greater acceptance based on the confinement method associ- ated with them. In other cases, GEOs could be viewed as less acceptable or even potentially dangerous because the associated confinement method in- dicates the serious risk posed by the GEO. It is premature to make predic- tions regarding public acceptance. However, the following case study of one bioconfinement method could provide some insight into the public's future response to bioconfinement. Case Study of the Technology Protection System: "Terminator" At the time the Technology Protection System was being developed, some seed manufacturers were requiring their customers to sign contracts prohibiting them from saving and reusing seed from cultivars with utility patents. Compliance was an issue, and the Technology Protection System seemed an ideal solution. The TPS was created through a Cooperative Research and Development Agreement (CRADA) signed between the U.S. Department of Agriculture's Agricultural Research Service and the Delta and Pine Land Company in 1993, and the developers jointly received a patent on the process in 1998 (U.S. Patent 5,723,765). The Rural Advancement Foundation International (RAFI; now the Action Group on Erosion, Technology, and Concentration), an NGO based in Canada that opposes the use of biotechnology, labeled the Technology Protection System "terminator technology." The NGO drew considerable attention to a potential impact of the system if it were to be applied: subsistence farmers who traditionally saved seed from one season to the next no longer would have that option. Seeds collected from their technology- protected GE crops would not be viable.

26 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS The traditional farming practice of seed saving is widespread and important to farmers throughout the world. The loss of the ability to save seed­­which could compromise food security for resource-poor farmers­­ was a concern with terminator technology. This concern resonated with the mainstream international media which helped publicize the issue. The con- cept of terminator technology and concern about its consequences for sub- sistence farming helped make this story much simpler to report than were other stories about genetic engineering (Lambrecht, 2001; Priest, 2001). The issue of seed saving had other ethical implications. A seed can be viewed as a living organism--and reproduction is an essential part of what living organisms do (Boorse, 1975). When one purchases a product, it is usually implicit that one is entitled to the full, normal functioning of that product (Cummins and Perlman, 2002). If reproduction is understood as part of the normal functioning of an organism, then that claim would extend to the offspring of the organism. Terminator technology for intellec- tual property protection has faced opposition for this reason (Eaton et al., 2001; Halweil, 2000). Widespread public debate about terminator technology ensued, and objections came from the Consultative Group on International Agricultural Research, whose members unanimously recommended banning research on terminator genes. Further criticism came from Gordon Conway, president of the Rockefeller Foundation (Lambrecht, 2001). Monsanto (who had sought to acquire Delta and Pine Land in part because of its 1998 patent on the system) subsequently announced that it dropped the technology. The potential impact on subsistence farmers was not the only concern associated with the terminator technology. The campaign of RAFI also claimed that the development of terminator technology was evidence that "life-science companies were bent on controlling the food chain" (Lambrecht, 2001). This argument is part of a larger, continuing debate about whether "biotechnology will help a few well-capitalized companies control decision making in agriculture and limit farmers' ability to choose from an array of production possibilities" (Thompson, 2000). Terminator and other "genetic use restriction technologies," also known as GURTs (see Chapter 3), have been linked with corporate interests in protecting intellec- tual property rights. The continued legal battles involving infringement reinforce this association, even in cases that do not involve such technology (Priest, 2001). Although there were sporadic attempts to highlight the utility of terminator technology as a tool for bioconfinement, there is no evidence that this was taken seriously, either as a motivation for the initial development of the technology, or by environmentalists. More recently, similar technologies have been developed for use in confinement rather than strictly for protection of intellectual property rights (McHughen, 2000).

INTRODUCTION 27 In summary, a lesson from the terminator technology experience is that social acceptability based on ethics can be a powerful influence on the decision to adopt or reject a bioconfinement method. A combination of efforts by numerous NGOs, activist organizations, and the media generated enough public opposition to terminator technology to persuade several companies and agencies to abandon it. In the future, will the response to related technologies and other reproductive methods of bioconfinement be different from the rejection of terminator technology? Are there alternative approaches to developing and characterizing bioconfinement methods that could be met with greater acceptance than terminator technology? This report describes many possible options for bioconfinement­­with the goal of stimulating constructive debate and discussion. Consequentialism and Public Acceptance The potential risks associated with the bioconfinement of GEOs can be understood within the framework of a major philosophical tradition­­ consequentialism­­which defines what is right for society in terms of maxi- mizing the net good. For confinement methods, acceptability is determined with objective values used in risk-benefit analyses. The consequentialist approach is implicit in much of the United States regulatory system, and is the reason for the focus on scientific risk assessment to analyze uncertain- ties with GEOs. However, as the experience with terminator technology illustrates, decisions about bioconfinement will take place in a social and ethical context that is not framed solely in terms of quantifiable risks (Thompson, 1997). Despite its influence on regulatory policy and international discussions, consequentialism does not account for all of the ethical issues raised about genetic engineering (Thompson, 1997) or specifically bioconfinement. Early confinement strategies and the system for their regulation that were devel- oped in the early 1970s focused on a narrower set of concerns that were best addressed by the scientific community. This approach was and remains appealing: the expectation is that clear, rigorous, and concise characteriza- tion of existing information about risks, costs, and benefits will lead to informed and acceptable regulatory decisions (NRC, 1996). Nonetheless, the narrow focus ignored potential ethical problems (Wright, 1994) and current approaches continue to ignore moral considerations in favor of science-based issues and utilitarianism (Saner, 2001). It is useful to recognize that the products of genetic engineering can be organisms that can have social significance or be infused with value for any number of reasons. For example, trees have important symbolic, social, and aesthetic values that present important challenges for biotechnology (McQuillan, 2000; 2001). The desire for "natural" (and even "wild") forests

28 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS would require stricter confinement methods than simple safety considera- tions would dictate. To ensure the purity of culturally significant crops, stringent confinement could be necessary. Beyond risk assessment, there is also the perspective that broader social and ethical values should be considered in determining how much and which methods of confinement would be necessary for various organisms. To address different value systems in bioconfinement decisions, considera- tion would be given to who is exposed, who benefits, and who decides. RAFI was effective in drawing the public's attention to these questions in the terminator case. The values of specific groups and communities could emerge as important considerations in the choice of biological and physical confinement methods. A consequentialist framework cannot accommodate the diversity of values in the debate. As a result, the framework can fail to incorporate much of the public's concern about genetic engineering and bioconfinement. Gaskell and colleagues (2002) draw on extensive data collected in the mid- to late-1990s about attitudes toward genetic technologies in the United States and Europe (Durant et al., 1998). There is a striking pattern in the responses that emerged about the risks, benefits, and moral acceptability of genetic engineering that led the authors to conclude "respondents with concerns about gene technology tended to think principally in terms of moral acceptability rather than risk" (Durant et al., 1998). Public acceptance of bioconfinement methods for GEOs will depend on many of the same factors that influence the public's acceptance of genetic engineering and its products. For bioconfinement to gain public acceptance it will be imperative that lessons are learned from the successes and failures of the past (Eichenwald et al., 2001). In addition to the science-based evaluation used to determine what, if any, confinement strategy should be applied to a GEO, the clear and public articulation of potential ethical concerns is likely to promote public trust and acceptance. Ultimately, the benefits of bioconfinement must be considered. The methods can be power- ful tools when combined with other physical, temporal, and biological measures to ensure that GEOs will not harm ecosystems or threaten the food supply.

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Genetically engineered organisms (GEOs) have been under development for more than 20 years while GE crops have been grown commercially during the last decade. During this time, a number of questions have cropped up concerning the potential consequences that certain GEOs might have on natural or managed ecosystems and human health. Interest in developing methods to confine some GEOs and their transgenes to specifically designated release settings has increased and the success of these efforts could facilitate the continued growth and development of this technology.

Biological Confinement of Genetically Engineered Organisms examines biological methods that may be used with genetically engineered plants, animals, microbes, and fungi. Bioconfinement methods have been applied successfully to a few non-engineered organisms, but many promising techniques remain in the conceptual and experimental stages of development. This book reviews and evaluates these methods, discusses when and why to consider their use, and assesses how effectively they offer a significant reduction of the risks engineered organisms can present to the environment.

Interdisciplinary research to develop new confinement methods could find ways to minimize the potential for unintended effects on human health and the environment. Need for this type of research is clear and successful methods could prove helpful in promoting regulatory approval for commercialization of future genetically engineered organisms.

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