Annotated Bibliography Entry

Reference: ICSU 2002
Title: Biotechnology and Sustainable Agriculture
Authors:  Persley, G.J., Peacock, J. and van Montagu, M. for the ICSU Advisory Committee on Genetic Experimentation and Biotechnology (ACOGEB).
Publisher: International Council for Science (ICSU), 51, Boulevard de Montmorency, 75016 Paris, France.
Publication details:  ICSU Series on Science for Sustainable Development No 6, 45p.

Summary
Commercial cultivation of transgenic crops
Emerging scientific discoveries
Understanding risks and benefits of gene technology
Conclusion
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Summary

The focus of the 2002 World Summit on Sustainable Development is on improving the relationship between human society and the natural environment. This document discusses the contributions and consequences of current and future applications of gene technology in agriculture, and the ways that these may affect human health and the environment.

Present contributions of gene technology to agriculture

The contributions of gene technology to today’s agriculture are already substantial. Discoveries in gene technology have led to:

·      Better understanding of how plants function, and how they respond to the environment.

·      More targeted selection objectives in breeding programs to improve the performance and productivity of crops, trees, livestock and fish, and post harvest quality of food.

·      Use of molecular (DNA) markers for smarter breeding, by enabling early generation selection for key traits, thus reducing the need for extensive field selection.

·      Molecular tools for the characterization, conservation and use of genetic resources

·      Powerful molecular diagnostics, to assist in the improved diagnosis and management of parasites, pests and pathogens.

·      Vaccines to protect livestock and fish against lethal diseases. 

It seems likely that in most countries the applications of gene technology to agriculture will be a two-stage process. Firstly, there are many applications of gene technology that can be used to improve the management and efficiency of present agricultural practices. Secondly, there are options for the targeted introduction of transgenic strains, genetically modified for one or more specific traits. Although transgenic strains of various species of crops, trees, livestock and fish have been developed experimentally, only transgenic crop varieties are in widespread commercial use in agriculture today.

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Commercial cultivation of transgenic crops

Broadly, the first wave of genetically modified crops, which are in commercial use, address production traits; the second wave, which are mainly under development, address quality and nutritional traits; and the third wave address complex stress response traits and novel products able to be produced in plants. The scientific basis of dealing with each of these groups of traits is increasingly complex.

The production traits targeted in the first wave of transgenic crop varieties specifically addressed the economic and environmental costs of agronomic practices and chemical management in large-scale agriculture. An important factor in the initial choice of production traits was the fact that the major early private investors in plant biotechnology were several multinational chemical companies. The long-term viability of chemically based agriculture was being questioned. A combination of new scientific possibilities, business opportunities, and decreasing viability of chemically-based agriculture led to the targeting of particular production traits (particularly insect resistance and herbicide tolerance) and their subsequent commercial development into new transgenic crop varieties.

The first transgenic plant was produced experimentally in 1983. The first commercial cultivation was in 1995. By 2001, there were almost 53 million hectares of genetically modified crops growing in thirteen countries. These crops are mainly soybean, corn, cotton and oil seed rape, with resistance to certain insects and/or herbicide tolerance. Many other crops and traits are under investigation but most have yet to be taken through to practical use.

 

Trait selection

The developers of the first generation of genetically modified organisms faced a number of technical limitations that influenced the choice of species and traits that have been taken through to full product development. The constraints include:

(1) The availability of genes controlling traits that could be manipulated. Initially only traits controlled by single genes could be manipulated. Most characteristics of food, yield, and responses to stress are complex traits, controlled by several genes.

(2) The efficiency of the methods to produce genetically modified organisms that express the desired trait consistently under field conditions;

(3) The need to meet evolving regulatory requirements for new crop varieties and other living modified organisms (LMOs) containing genes from outside their normal range of hybridization.

Management of single gene production traits: The careful targeting and correct management of single gene traits is critical for their successful use in agriculture, so as to avoid the boom/bust cycles typical of single gene resistance. In the deployment of new transgenic varieties of Bt-crops, such as cotton and corn, in broad scale agriculture, much effort has gone into devising and implementing specific crop management arrangements that lessen the pressure for the evolution of resistance in the target pest. These crop cultivation regimes include leaving some of the field as non-transgenic, susceptible crops (providing refugia for the insects) or to include in the plant two or more different genes for pest resistance (gene stacking).

 

Dealing with complex traits

Emerging scientific developments are enabling complex traits to be addressed, with the intention of developing new products of potential value for agriculture, human health and the environment. The attractiveness of the new targets is tempered by the fact that they are technically difficult, requiring the expression and control of multiple genes, often involved in different biochemical pathways. The new targets include traits for:

Increasing sustainable agricultural production, by the cultivation of crops that are better able to tolerate biotic stresses (pests, diseases and weeds) and abiotic stresses (drought, salinity, and temperature stress).

Delivering health benefits through more nutritionally beneficial foods, with higher content of essential vitamins and minerals, especially in staple crops; and reducing allergenic, carcinogenic and/or toxic compounds in certain plants.

Using plants for pharmaceutical production: More economical and efficient production of vaccines against human diseases, and other pharmaceuticals in plants.

Using plants for production of products for industrial purposes: including novel compounds such as biodegradable plastics and industrial strength fibers.

Environmental benefits: Using plants (and microbes) to mitigate the effects of industrial pollution (bioremediation), by increasing their ability to remove and/or break down toxic compounds in the soil.

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Emerging scientific discoveries

Recent scientific developments confer the ability to study the structure and function of all the genes within an organism simultaneously (through genomics), as well as the protein products they code for (through proteomics). It is also possible to study the role of all the chemical compounds in the metabolism of the cell (through metabolomics). These emerging scientific developments are being greatly assisted by powerful computing and statistical techniques that enable the assembly, interrogation and interpretation of large databases (through bioinformatics). New terms are being coined to describe these rapidly evolving branches of science and the techniques on which they are based.

The emerging scientific possibilities also pose new challenges in the assessments of the risks and benefits of potential new products to human health and the environment. Some of the potential products are meant for food or feed use, while others are intended for use as pharmaceuticals, and others as compounds for industrial uses. Some will require inter-specific transfer and control of multiple genes. Others will rely on switching on (or off) and better regulating genes that are already present in the organism but not usually expressed.

The new scientific developments also offer potential means to overcome some of the risks in the cultivation of genetically modified crops. These include limiting the unintentional movement of genes out of the target crop (through gene containment); better food safety assessments of unintended changes in the composition of foods by assessments of the content of whole foods (through metabolomics); and the removal of antibiotic resistant, selectable markers from GM foods.

The challenge is how emerging scientific discoveries, such as those in the rapidly evolving fields of genomics, proteomics and metabolomics, amongst others, can be translated into safe applications of biotechnology that will lead to new varieties of crops, novel foods and new products that deliver benefits for society. These new applications and their risks and benefits will differ in different parts of the world.

Careful thought needs to be given to identifying the most suitable targets and desirable traits for future research and development efforts, in different countries and environments.

New understanding of plant and animal genes through genomics: Genomics refers to the processes used in identifying the location and function of all the genes contained in an organism. This new knowledge will change the future of breeding for improved strains of all domesticated species of crops, livestock, fish, and tree species.

Twelve crops, five livestock and two fish species provide over 90% of the world’s food. For these staple species, national and international public sector research has made a large investment in genetic resources and breeding materials, and has an understanding of their behavior in different environments. These scientific and biological resources will become increasingly important in gaining knowledge about the function of genes, in developing molecular markers and other means to assist in the breeding of improved strains.

The first plant genome that has been completely sequenced is a small, model species, Arabidopsis thaliana. The genomic sequencing of economically important crops is also being undertaken. The most advanced are the several public and private gene sequencing projects on rice, all of which are now in the public domain. A maize genome-sequencing project is also in progress. Rice, maize and other cereals share a large number of common genes. Several other genome sequencing projects of at least 120 different plant species are in progress.

Understanding the role of proteins through proteomics: Most cellular functions are carried out by multi-protein complexes. New techniques are enabling these complexes to be unravelled, and the functions of individual proteins understood. These techniques allow the identification and quantification of proteins expressed in a particular tissue or in a specific developmental or environmental condition, such as in response to stress.

Understanding what happens in the cell through metabolomics: Information on metabolite levels in the cell is critical to obtaining an overview of a biological process. Examining changes in metabolic profiles is an important part of assessing gene function and relationships of phenotypes. Modern high-resolution techniques allow the establishment of a profile of all metabolites present in a specific plant tissue. A variety of previously unidentified biochemical pathways can now be understood. Metabolomics can also provide information on metabolic network regulation in response to genetic and environmental perturbations, leading to a better understanding of plant responses to stress. Extensive databases of quantitative information are being developed about the degree to which each gene responds to environmental stimuli, such as biotic and abiotic stresses. These databases will provide insights into the set of genes that control complex responses and will create powerful opportunities to assign functional information to genes of otherwise unknown function

Metabolic engineering: Metabolic engineering is the in vivo manipulation of biochemistry to enable plants to produce non-protein products or to alter cellular properties. The products may be native to the plant or novel (expressed after the introduction of genes from another source). Recent research shows that it is technically possible to produce the following products in plants at the experimental level: Vitamin A precursors; essential oils; medicinally important alkaloids; biodegradable plastics; vaccines. Several of these products are now in development phase and are coming forward for regulatory approval.

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Understanding risks and benefits of gene technology

The rapid increase in the use of new techniques for understanding and modifying the genetics of living organisms has led to greatly increased interest and investments in biotechnology. These developments have been accompanied by public concerns as to the power of the new technologies and the safety and ethics of their use for improving human health, agriculture and the environment. 

Public concerns about the applications of biotechnology lie in four major areas: (1) Ethical issues; (2) Socio-economic effects; (3) Food safety and human health; and (4) Impact on biodiversity and the environment. In agriculture, these concerns relate particularly to the release of living modified organisms (LMOs) for agricultural purposes. These organisms may be plants, trees, livestock, fish and/or microorganisms.

The ethical issues relate to moral and social concerns about the nature of gene technology itself and the consequences of its use in specific situations. There are concerns about the appropriateness of the use of intellectual property rights in relation to living organisms, and means to ensure the equitable sharing of benefits by holders of genetic resources, owners of indigenous knowledge and inventors.

Socio-economic effects are concerned with the economic risks and benefits in the use of new biotechnology applications, the implications of intellectual property management on agriculture in different countries and in identifying who gains and who loses from the use of new technologies in various circumstances.

In relation to food safety and human health, there are concerns as to assessing the risks of genetically modified foods to human health, in the short and long term;  identifying specific nutritional benefits of genetically modified foods developed for this purpose; and searching for any unintended effects of genetic modifications on food.

In relation to impact on biodiversity and other possible environmental effects, the concerns relate to assessing the risks and benefits of releasing living modified organisms into the environment, and the effects such releases may have on the environment. These effects may be through direct effects on the environment, including potential impact on biodiversity, and/ or indirect effects through changing agricultural practices that affect the environment.

Consideration of all these issues, on a case by case basis, provides a basis for choices on the merits and safety of the applications of new biotechnologies to address particular problems, relative to existing agricultural technologies and other technology options. All these issues are important in making choices on the use of gene technology to address particular aspects of sustainable development. This document addresses specifically the emerging scientific trends; the scientific basis of assessing the effects of gene technology on food safety and human health; and the impact of gene technology on biodiversity and the environment.

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Conclusion

Achieving the potential applications of modern molecular science will require substantial private and public investments, and a wide range of scientific skills. These required skills lie not only in gene technology, but also in the related fields of plant breeding, agronomy and physiology, food and nutrition and in natural resources management. There also needs to be greatly improved linkages amongst the social, scientific, industrial and environmental communities, so as to better define the ways in which science can benefit society and to design new technologies in ways that are socially and environmentally acceptable and beneficial in different countries and communities.

New developments in science and technology, including the continuing discoveries in gene technology, can contribute to achieving strategies for sustainable development, if they are:

·      Directed at clearly defined targets that affect poverty reduction, food security, environmental conservation and/or trade competitiveness;

·      Accompanied by political will, supportive public policies, and public and private investments in both science and technology and product development and delivery;

·      Implemented under the auspices of transparent regulatory frameworks that generate public trust and confidence in the safety and ethical use of new biological products and processes for human health, agriculture and the environment.

This overview document will be complemented by a meta-review commissioned by ICSU that is analysing the key findings of reviews on GM foods and crops that have been conducted by various national, international and private agencies within the past three years. Particular attention is being given to identifying the areas of commonality amongst the reviews, identifying any areas of differing perspective, and highlighting those areas where there are gaps in knowledge that may be able to be addressed through additional well targeted research. 

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