Science Concensus Conference: Unnatural dilemmas for a hungry world

AGRICULTURE is on the brink of a revolution. A startling and potentially potent force for change is on its way. At its heart is the science of genetic engineering. This, in the form of the new industry of biotechnology, promises to turn agricultural production on its head, in the developing nations as well as the West.

Researchers around the world are using plant biotechnology to create new species unknown to nature. Their work is producing strange new crops, with genetic material, or DNA, stitched into their own coded genomes from other plants, from bacteria and viruses, even from animals.

These 'designer' crops challenge the precepts of agriculture in a way that was hardly imaginable a few decades ago. And it is not just agriculture that the new crops will upend. Genetically engineered plants hold potential for medicine in the production of drugs, and for the process industries in the manufacture of oils and plastics.

The science that will bring all this about is proceeding apace. Already, research has produced crop plants, from beetroot to strawberries to walnuts, that can survive frost, resist insects and fend off disease. Others have been engineered with an immunity to herbicides - allowing farmers to spray their fields for weeds, safe in the knowledge that their crops will remain intact.

Some food crops sound like the product of a stimulated imagination: fatter trout with added genes that make them produce human growth hormone, frost-resistant tomatoes with fish genes slotted into their DNA code, potatoes with added genes from intestinal bacteria that render them crispier for frying as chips. Yet all of these are real. And it is not only crops, but the pesticides used to protect them that are part of the revolution. Scientists in Oxford have engineered a controversial viral pesticide with extra genes for scorpion venom, designed to attack caterpillar pests.

Other researchers have boasted of their success in creating tobacco plants with extra nicotine content and roses created in the laboratory to a colour code - blue perhaps, or maybe black is more stylish.

These are the more outlandish fruits of the genetic engineering of plants. Other teams are working on products with more obvious benefit, including staple crops that can grow in inhospitable climates such as those with little rainfall, or in salty soils; crops with higher protein or vitamin content; others that can make maximum use of nitrogen in their soil.

It is a cruel irony of nature that staple crops, such as wheat, rice and maize, have proved technically more difficult to alter by genetic engineering than plants such as tobacco and oilseed rape. Yet these staples hold real potential to contribute to the efforts of developing countries to grow more food with greater nutritional value. Sustained research effort is at last beginning to pay off, and recent results have proved encouraging. Last month, British researchers engineered plants that will grow, and produce useful harvests, in shaded areas where crops normally prove poor and straggly.

So much for the science, but what does society really want? Public debate of the possibilities and implications of plant biotechnology is only now beginning, which makes the Science Museum's 'Consensus Conference' an important experiment. The organisers believe this is the first time Britain has used this approach to scrutinise a scientific subject with broad social relevance. The idea is for a panel, comprised of members of the public, to look specifically at the social, political and ethical issues thrown up by the scientific and technical advances of plant biotechnology.

Perhaps prime among these is the philosophical dilemma. The biotechnology industry often argues that there is little difference between the traditional breeding techniques that have produced strong crops in the past and the new techniques which they say simply allow them to push advances further and faster. But gene splicing can legitimately be described as a quantum step. It allows a transfer of genes not only between one plant species and another, but between plants and animals, plants and bacteria, and plants and viruses.

Gene transfer now knows few boundaries. Genetic engineers can slot human genes into other animals, fish genes into plants. This intermingling of genetic material would not take place under 'natural' circumstances. Moral philosophers are starting to ask whether humankind should be tinkering with the stuff of life in this way.

Then there are social and industrial considerations. Of the food products currently being engineered, about 98 per cent are being altered to make them easier to grow (crops with herbicide resistance) or process (McDonald's and DuPont are working on celery and carrots engineered by selection to stay crisp and Safeway has funded engineering of lettuces to produce individual serving-size heads). Only 2 per cent offer direct benefit to the consumer, say, through improved nutritional value or taste, although industry argues that any production savings it makes will be of indirect benefit to customers.

Some argue that biotechnology discourages diversity in agriculture and concentrates power in the hands of a small number of conglomerates. Herbicide producers are tying up deals with the producers of the resistant crop, creating a monopoly that some believe will push out small farmers and agricultural businesses. In the US, almost 80 per cent of the genetically engineered foods proposed for field testing have been developed by industry. Five transnational companies - Monsanto, Upjohn, Frito-Lay, Calgene and Pioneer Hi-Bred - account for more than half these products.

The panel might also consider environmental objections to some of this work. Much of this anxiety springs from the fact that scientific knowledge of the ecological impact of these new plants is very limited. Nobody knows how man- made plants will behave once they are planted out among their natural counterparts. Ecologists are only beginning to examine possibilities such as how far pollen from engineered plants will travel, whether this fertilises other plants and if it transfers the foreign genes it carries to other crops. If, for instance, herbicide-resistant genes spread to weeds, these could develop resistance of their own (just as bacteria have developed resistance to antibiotics). Besides, the development of herbicide-resistant crops encourages the use of chemicals, when we should be cutting down on these, they say. An engineered plant might also become an invasive pest, forcing out natural species. Some environmental groups and scientists question whether safety controls to prevent such scenarios are sufficient.

Others are concerned at the commerical implications of the work. In other areas of science and engineering, patents are one way of acknowledging investment of expertise and money in innovation. Patents also establish a route by which developers can recoup their costs. But should individuals or commerical organisations be allowed ownership of new lifeforms, even if they did create them? One US company has already patented all engineered varieties of cotton, and soybean. Scientists also fear that patenting will hamper the free exchange of research information so precious to their working lives.

How should the products of this revolution be labelled, if at all? Should food with bits of animal genes in it carry labels to inform vegetarians, or food with added pig genes be marked so those with religious objections can make choices?

As the panel considers plant biotechnology, and possible regulations and controls, they may stray into broader discussion of genetic engineering techniques in manipulating animals. Scientists are already producing useful drugs that are contained within the milk or blood of rabbits, pigs, sheep and goats given extra genes at embryo stage. Pharmaceutical Proteins, an Edinburgh-based company, has developed sheep that produce useful proteins in their milk, such as blood-clotting Factor IX and a drug for treating emphysema, the lung disorder.

This work, perhaps more than any other, illustrates the dilemmas the new biotechnology poses for all of us. To some, these engineered animals are repulsive, biological drugs factories. To the families of those suffering life-threatening diseases, the same work holds the promise of cheap, life-saving drugs and new hope. This daunting range of questions will form the core of the thinking and debate of the Science Museum's panel over the next three months, as they weigh up the benefits and risks of this challenging new science.

(Photograph omitted)