Q J Med 2003; 96: 779-780
© 2003 Association of Physicians
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Before Frankenstein
In the current debate about the skilfully blackguarded ‘Frankenfoods’, the contrast between polemics and the rational documentation produced by the advisory panel chaired by Sir David King is stark. But it is clear that this panel-derived advice was hard to produce; there were clear tensions and one member of the panel resigned during the process. I will not comment on this debate (as the editor knows, I have been consulted by the industry about the risks that some believe may be related to this technology), but I thought it might be informative to look at a previous radical change in agricultural practise to see if the then-prevailing attitudes inform us about our current difficulties.
The ‘Green Revolution’ can be said to have operated from the late 1950s, when modern, high-yielding crop varieties were developed with the intention of benefiting developing countries. New varieties of rice and wheat were rapidly adopted in areas with good rainfall or irrigation systems in tropical and sub-tropical countries, and one measure of the success of the programme 40 years on is that currently the Consultative Group for International Agricultural Research (CGIAR) supports about 8500 scientists in 16 centres and has an annual budget of $3400 m. Here is the first and perhaps most critical point about these programs—they were carried out by international agricultural research centres (initially by the International Centre for Wheat and Maize Improvement in Mexico and the International Rice Research Institute in the Philippines) and were perhaps perceived as an activity for the ‘public good’ rather than a commercial venture. In general, there was little input from developed countries.
A study on the breeding, release and diffusion of 11 major food crops over the 40 years between 1960 and 2000 has been published.1 The programme began when plant breeders used native stocks to incorporate dwarfing genes in both wheat and rice to allow the development of shorter, stiff-strawed varieties that put their energies into producing grain, not leaf or stem. Importantly, these varieties also responded better to fertilizers. After the initial success with rice and wheat, other crops were developed, but there was no real database on the characteristics of many of the potential targets (such as cassava and tropical beans), making selection difficult. Years of development resulted in new forms of sorghum, millet and barley to be grown primarily under semi-arid and dryland conditions, and of pulses and root crops (notably cassava). The revolution came late to sub-Saharan Africa, where maize and rice were modified in the 1980s.
So we have a situation where a pattern of deliberate modification of crops and their wide introduction into environments that they may alter has been seen as a benefit rather than as a problem. However, acceptance of the new crops was not immediate. Farmers in sub-Saharan Africa were slow to adopt the varieties that had been developed for other areas—not until locally adapted germ-plasm had been used to breed new varieties did farmers identify them as valuable. It was necessary to demonstrate a benefit to farmers, and this needed to be considerable. It was estimated that the first generation of new rice was planted in around 35% of irrigated and rain-fed land in India. Subsequent modifications to induced disease and pest resistance increased planting to around 80%.
It is important to note that most of the benefit of the Green Revolution came in the 1980s and 1990s, when many would have said it was over. This emphasizes the evolutionary nature of the changes produced, which allowed food production to increase radically with only modest increase in the amount of land in agricultural use and with moderate increments in inputs of fertilizer.
In an attempt to determine what would have happened if there had been no Green Revolution, and if there had been no international effort in the field, some simulations were made by an impact assessment from CGIAR. It was considered that agricultural productivity in developed countries would have continued to increase (lower production in developing countries would have raised prices and made farming a better investment), that there would have been an increase in the area cropped (higher prices would drive this) and that there would have been productivity gains in the developing world in any case. But calorie intake per capita in the developing world would have been 13–14% lower, and more food would have been imported by those who could ill-afford to import it. Estimates are that the Green Revolution improved the health status of 32–42 million children.
The downside? Chemical intensivity developed, soil degradation occurred, aquifer depletion has been documented, and increasing soil salinity has also been attributed to the ‘new’ agriculture. But no one has suggested an alternative method that would have ensured that extra mouths would have been fed. Choices about crop use were mostly made locally.
The public good versus commercial benefit arguments have perhaps been the most obvious distinction between current rows about GMOs and the large-scale manipulation of the environment that the Green Revolution has brought about. The evolutionary aspect of the programme eased its acceptance in the local environment, and the importance of the farmer in the relevant environments clearly affected uptake. Here is a potential common ground: the rapid spread in India of genetically modified cotton, with its improved yields and low pesticide requirements, appears to be farmer-driven.
Most of us are remote from any aspect of food production; growing vegetables as a hobby with the assurance that a crop failure will not lead to starvation or penury gives little insight into the attitudes of those who might be affected in this way. It seems that a perceived benefit is the key, for the farmer this may be represented as income—or interestingly, an ability to send children (mainly girls) to school rather than the fields. Increased biodiversity from diminished pesticide use is not often a preoccupation of the subsistence farmer but is a concern of society at large. The muddled thinking that surrounds the ‘problem’ of DNA transfer (most people believe there is no DNA in natural food and few believe that they have acquired many new DNA sequences during their life) confounds a proper evaluation of risks. So for consumers, the likely benefit of a modified crop will not be thought to be large unless they live in an area of potential deficiency (vitamin A enhanced ‘Golden’ rice is the perfect example). Enhanced anti-oxidant content will not have the same effect on perception (even if it is of benefit—see reference 2).
The distinction between efforts to improve food production and the commercially-driven use of GM crops will blur in areas where benefits are seized upon by farmers. With more than 100 m Ha of GM crops planted around the world, many of the questions about gene escape and bio-diversity and pesticide use will be answered by observation. It will be interesting to see if the view of the European public about food crops changes with time—if the objections are to do with manipulation per se, it may not. Most of the concerns about hazards (there are few data that allow them to be described as risks) will be resolved by observation.
Perhaps the use of GM in therapeutics will alter things. The study of Steidler et al.3 shows how an effective therapy can be controlled in terms of many of the concerns expressed by those who worry about escape. A modified Lactobacillus lactis supplies interleukin 10 to those with inflammatory bowel disease, the transgenic bacteria are restricted to the target area by a specific strain dependency, and dissemination of the transgene is prevented. This technology can be controlled.
References
1. Evenson RE, Gollin D. Assessing the Impact of the Green Revolution, 1960–2000. Science 2003; 300:758–62.
2. Berry C. Functional foods. Q J Med 2002; 95:639–40.
3. Steidler L, Neirynck S, SnoechV, Vermeire A, Goddeeris B, Cox E, Remon JP, Remaut, E. Biological containment of genetically modified Lactobacillus lactis for intestinal delivery of human interleukin 10. Nature Biotechnol 2003; 21:785–9.[CrossRef][Web of Science][Medline]
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