The impact of 'terminator' technology
Bert Visser, Ingrid van der Meer, Niels Louwaars,Jules Beekwilder and Derek Eaton
Keywords:  Genetic Engineering, Intelectual property rigths (IPR), Risk assessment, Biodiversity, Seed.
Correct citation: Visser, B.; van der Meer, I.; Louwaars, N.; Beekwilder, J. & Eato, D. (2001), "The impact of 'terminator' technology." Biotechnology and Development Monitor, No. 48, p. 9-12.

Genetic use-restriction technologies enable the developers of transgenic plants or animals to protect their variety or breed from unauthorized use in a biological way. The use of 'terminator technology' can have different impacts on farmers and breeders. If the technology is effective, it impacts on agrobiodiversity and environment. This article focuses on the technology and its environmental effects.

In March 1998 the US Patent Office granted the US patent 5,723,765 on the "Control of Plant Gene Expression" to Delta and Pine Land Co. and the US Department of Agriculture. The patent describes a set of interacting genetic elements that allows the controlled expression of value-added traits or of seed viability in a crop plant. Control of the expression may either rest with the owner of the plant variety or with the farmer who grows the variety.

The Rural Advancement Foundation International (RAFI), now called ETC group, subsequently coined the term terminator technology to stress one of the likely applications of this technology which is that it becomes possible to grow crops which have seeds that are viable when sold to the farmer, but of which the seeds from the subsequent harvest are sterile. As a result, farmers would be unable to maintain a commercial variety from their own seed stocks and would be forced to return to the seed provider. In an earlier study by Richard Jefferson and co-authors for the secretariat of the Convention on Biological Diversity (CBD) on the consequences of the new technology, the term Genetic Use Restriction Technologies (GURTs) was proposed.

At the request of the Food and Agricultural Organization of the United Nations (FAO), the authors of this article recently carried out an in-depth study into the potential impacts of GURTs on agrobiodiversity and agricultural production systems. This article highlights some of the main conclusions of this study, including an assessment of the state-of-the-art of the technology, its likely effects on agrobiodiversity and biosafety considerations. In the next issue of the Monitor the potential economic consequences will be dealt with in more detail.

Genetic Use Restriction Technologies

A substantial number of patent applications now describe various GURT concepts and elements. Two types of technologies can be distinguished. On the one hand, technologies can restrict the use of a specific trait by regulating its expression (T-GURTs). In T-GURT concepts, one or more genes conferring a single trait are switched on or off at will through chemical inducers. The seed itself remains viable.

On the other hand, technologies can restrict the use of the entire variety through interference with reproduction (V-GURTs). Three types of V-GURT strategies can be distinguished.

It is important to realize that, although current patent applications apply to plants, GURTs can be built into any organism, including farm animals, fish and forest trees.

Other methods that share some degree of 'use restriction' with V-GURTs are hybrid technology, but also triploidisation and the introduction of male or female sterility. Differences between these latter technologies and V-GURTs are that the germplasm remains available to farmers and competing breeders for further breeding. In other words, if V-GURTs can be made sufficiently effective, they largely rule out the Breeder's Exemption and the Farmer's Privilege on the use of protected varieties as described in Plant Breeder's Rights.

Potential targets of GURT applications

Sector Trait examples Remarks
Wheat Nutrient quality; taste; yield; disease resistance; drought avoidance; cold tolerance. Staple crop; increased R&D expected
Rice Staple crop; increased R&D expected
Maize Staple crop/specialty products;gene flow containment desirable
Soybean Nutrient quality; feed quality
Cotton Agronomic traits; colour Increased R&D expected
Oilcrops Fatty acid composition Sunflower, olive, oil palm; Canola: gene flow containment (V)
Horticultural crops Quality traits V-GURTs for non-hybrids
Plantation crops Agronomic traits Coffee, banana
Cattle Meat quality; feed conversion efficiency Specialty products (pharmaceuticals)
Trees Environmental concerns; health benefits; lignin content Eucalyptus, Populus, Pinus, Acacia
Fish and other aquatic species Environmental concerns; yield; low-temperature tolerance; disease resistance Salmonids, carp, tilapia, crustaceans, molluscs

Motives for GURTs

The application of GURTs can be inspired by different, not mutually exclusive motives. These motives fall in the following categories.

It is important to distinguish between the impacts of GURTs on farmers vis--vis those on breeders. It is more likely that access to technology circumventing GURT protection will be more available to breeders than to farmers. Farmers will have fewer options to choose from.

Will GURT application be successful?

The increasing pace at which genetic information from genomics research is becoming available will most likely result in several effective GURT prototypes within five to ten years. Still, several bottlenecks in current concepts will prevent the application of GURTs in a number of cases. A major one is the requirement for watertight regulation of the genes. For instance, if a lethal gene is not only expressed after induction but also continuously at a low level, this may decrease seed viability.

A number of technical factors will determine for what purposes, on which crops, trees, farm animal and fish breeds, and on what time scale GURTs will be developed and applied. Costs to solve technical bottlenecks as well as costs stemming from regulatory requirements will be juxtaposed against expected rates of return when decisions are made on investments in GURT development. Application of GURT in crop breeding can be expected to precede its applications in the breeding of trees, fish and farm animals, as is also reflected in current patent applications. Options for introduction of GURTs in tree species are technically similar to those in crops. Applications in aquatic species may also emerge soon, although economic and environmental issues, such as the threat to survival of local indigenous fish populations with which the transgenic fish can interbreed, may result in a slower or more restricted development. The application of GURTs in animals currently experiences much higher technological as well as ethical barriers. Currently, breeding efforts focus on crops and animal breeds for which hybrid technology, triploidisation, male or female sterility and/or the legal provisions of intellectual property rights (IPRs) are available. A major influence of GURT availability might be a shift towards crops and animals with the largest market shares or highest profit margins since the appropriation of breeding investments by the use of GURT will be independent of availability of those other technologies.

Furthermore, it can be envisaged that T-GURTs will prove to be more widely acceptable and technologically less demanding than V-GURTs because control may be less absolute.

Stakeholders and impacts on agrobiodiversity

The way in which the conservation of agrobiodiversity has been 'organized' has major consequences for assessing the potential impact of GURTs on agrobiodiversity and agroproduction systems and justifies a stakeholder analysis.

Stakeholders encompass the public and private sector, as well as farmers and supportive non-governmental organizations (NGOs). Obviously, each of these stakeholders has different roles and interests. For example, the private sector largely maintains its own ex situ collections of germplasm and other commodities or has ready access to such stocks, while autonomous farming systems only marginally rely on external sources of germplasm and other commodities and largely maintain their own knowledge system. Stakeholders in the private sector do not generally consider it to be a priority to maintain agrobiodiversity in autonomous farming systems, or to ensure the survival of wild relatives in natural ecosystems as a much wider source of genetic resources. Although the private sector may regard genetic diversity in such farming systems as highly relevant in the long run, it is often regarded as being mainly a public, long-term responsibility.

With increasing GURT application, access for autonomous farming systems to novel industrial innovations under GURT control will become limited or even absent. The degree to which this phenomenon will affect these farming systems will be dependent on their current use of such new traits and varieties. In other words, the issue at stake here is the genetic overlap: which crops and animal breeds form major constituents of both industrial and autonomous farming systems? To what extent does industrial and autonomous production under similar agroecological conditions result in breeding investments in varieties and breeds used by both sectors? Which of the traits developed by the private sector are relevant to small-scale producers?

At first sight, interference between GURT development and the maintenance of agrobiodiversity may seem limited. However, on a larger time-scale effects may be substantial. Farmers in autonomous production systems mainly rely on their own seeds and animals adapted to their particular agroecosystems, their farming practices and cultural preferences. This does not mean that there is no utilization of varieties and breeds stemming from the private sector. On the contrary, as far as accessible, these varieties and breeds are used by farmers to test them under their own conditions and - if suitable - to recombine them with their own germplasm to improve and 'breed' new varieties and breeds. In addition, the public sector, the national agricultural research systems (NARS) and the institutes of the Consultative Group on International Agricultural Research (CGIAR), act as a channel by which major genetic improvements developed in the private sector can reach autonomous farming systems. In conclusion, crop development in farmers' seed systems may miss options for crop development available to industrial seed systems due to limited access to new traits and varieties protected by GURT.

Environmental effects

Negative effects on yields of outcrossing from V-GURT containing varieties to neighbouring crop stands may occur. The size of these effects will depend on the outcrossing rate of the crop concerned, and on the physical distance between donor and acceptor plants, related to the intensity of the farming systems. These negative effects will also occur in those cases in which VGURT strategies would be consciously employed to prevent unwanted gene flow from genetically modified organisms (GMOs) into the environment, cultivated or wild, as an approach to avoid undesirable effects of a deliberate release of GMOs. Such negative effects are most likely to occur in outcrossing crops and trees. The probability might be the highest for trees because of the ability of pollen to disperse over long distances. However, negative impact may be low assuming that tree seeds do not form an economically important product.

Potential negative environmental effects in animal husbandry can be avoided more easily, in view of the high level of domestication and current farm practices to control reproduction. In contrast, the transfer of GURT constructs into wild fish populations with potential negative effects on population survival might be substantial because of the low level of domestication and the high probability of escapes of fish varieties.

For T-GURTS, the impact of outcrossed constructs will be limited in most cases. It can be expected that most GURT-protected traits will be under the positive control of a chemical compound, a so-called inducer. If such a construct would outcross to other crops to which the chemical is not applied, the construct will usually remain unnoticed. However, such constructs may still survive and exceptions to this rule can be imagined. First, the trait could be induced by a range of related compounds or triggered by naturally occurring events, such as steroids, pest and disease infestations. Second, the receiving organisms could already contain a GURT construct controlled by related inducers so that the inducer would activate both constructs. Such undesirable effects might be avoided by choosing highly specific inducers.

A third and more problematic scenario is the outcrossing of GURT constructs that exhibit negative control of the involved trait. This means that a trait is expressed unless it is blocked by the application of an inducer. In the case of outcrossing, the chemical compound would most likely not be applied to the organism that newly integrated the construct and the trait would be continuously suppressed, also when not desired. Such outcrossing could affect not only domesticates but also wild relatives.

Although individual elements of a GURT construct may outcross independently and exhibit certain effects, the likelihood of such events is very low, since these assume both a recombination event and an outcrossing event in most cases. In other words, such elements will only outcross separately from the other elements of the same construct, once they have been physically separated from each other in the genome.


To safeguard long-term on-farm conservation and development of plant genetic resources, increased investments in public plant breeding, including participatory plant breeding may be needed to correct the increasing gap in absorption of innovations by autonomous farming systems. This is most important for all staple crops and major vegetables and fruits grown in industrial and autonomous farming systems. Similar assumptions can be made for applications of GURTs in the other agricultural sectors. In particular in aquaculture, some species such as tilapia and crustaceans are grown in both small-scale and large-scale systems. The growing dependence of the small-scale sector on seed developed and provided by industry may have negative effects on the biodiversity of species maintained in aquaculture. Alternatively, the small-scale sector might have to rely completely on its own germplasm improvement, thereby restricting genetic resources development. Applications of V-GURTs in crops, whether to protect investments or to protect the environment should be assessed for their negative yield effects. Also, the probability of negative effects on local fish populations and tree relatives of transfer (introgression) of V-GURT constructs warrant further study. The impacts of negatively regulated traits with undesirable effects on yields and quality in a wide sense may need further discussion and policy development.

The use of some compounds as inducers, for example steroids, may have to be regulated, like pesticides and veterinary medicines, depending on the nature of the compounds. Their effects on the target organisms as well as the environment and human appliers and consumers need to be assessed.

Bert Visser*, Ingrid van der Meer, Niels Louwaars,Jules Beekwilder & Derek Eaton**

*Centre for Genetic Resources the Netherlands and Plant Research International, P.O. Box 16, 6700 AA Wageningen, the Netherlands.
Phone (+31) 317 477184; E-mail L.Visser@plant.wag-ur.nl

** Agricultural Economic Research Institute LEI, The Hague, the Netherlands.

This article is based on a study carried out on the request of FAO, and co-financed by FAO and the Netherlands Ministry of Agriculture, Nature Management and Fisheries through the Agricultural Research Department DLO. It is the sole responsibility of the authors. The study material was used as a background for the preparation of the FAO document referred to below. A full version of the study material will appear as FAO Background Document.

FAO position on the potential impact of GURT. http://www.fao.org/waicent/FaoInfo/Agricult/AGP/AGPS/pgr/itwg/pdf/P1W7E.pdf

Rautner, M. (2000), "Designer Trees" Biotechnology and Development Monitor, No. 44/45 , p. 3-7.

Contributions to the Biotechnology and Development Monitor are not covered by any copyright. Exerpts may be translated or reproduced without prior permission (with exception of parts reproduced from third sources), with  acknowledgement of source.


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