Feb 24, 2006

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Second and third generation GM plants

Sober outlook

The Office of Technology Assessment at the German Parliament (TAB) has presented a comprehensive study on "second and third generation genetically modified plants". The report paints a somewhat bleak outlook. Only a handful of the new GM plants are likely to be used commercially in the near future. Many projects are still at an early stage of research and development, making it "impossible to give a realistic prognosis as to whether they will ever be ready for practical application."

Herbicide and insect resistance - Genetically modified plants with new agronomic characteristics can now be found growing in fields throughout the world. Plants which have been genetically engineered to produce new, high-grade products, on the other hand, are extremely rare.

GM plants for supplying enhanced foods: Marketable products are some way off at present (Photograph: Vitamin-enriched Golden Rice)

GM plants for supplying new renewable raw materials: Still at an early stage (Photograph: Potatoes with modified starch composition)

GM plants for supplying active pharmaceutical ingredients: fifteen substances already undergoing clinical trials.

The TAB report examines how far advanced the development of these second and third-generation GM plants actually is, what are the chances of bringing them to market and whether existing strategies for safety assessment are adequate for these plants. The final report was received with great approval by the Bundestag Committee for Education, Research and Technology Assessment on the 15 February 2006. The report is based on several expert opinions and studies. It deals with genetic modifications to plants which are aimed at new product characteristics and applications as opposed to agricultural cultivation methods. This includes for example plants which provide foods with added health benefits or renewable raw materials. It also covers “pharmaplants”, which are used as biological production systems for manufacturing high-grade active pharmaceutical ingredients.

Different stages of development. The TAB report comes to different conclusions about the different areas of application of new GM plants.

• GM plants which produce food with enhanced product characteristics
  Several such GM plants which have been cultivated in the USA, have since disappeared from the market, for example tomatoes with delayed ripening or rape and soya beans with modified fatty acid composition. In fact, although various GM plants containing substances with added health benefits (functional foods) have been developed, so far they have mainly been prototypes, which have yet to be feasibility tested. At the moment marketable products still seem to be some way off.
• GM plants which produce industrial raw materials (renewable, raw materials, PMIs or plant-made industrials)
  In this particular area there were high expectations of extending the use of the plant as a “biological system” through genetic engineering. Although the first product, a GM potato with modified starch composition, is currently in the European licensing system, a commercial application of similar projects still seems some way off. The actual stage of development of GM plants with “tailor-made” fatty acid or starch composition, for example, is as difficult to gauge as it is for plants designed to produce industrial enzymes or biopolymers (“bioplastics”). The reasons vary from case to case. The development of new plants clearly needs more time than originally envisaged. In some cases there have been difficulties in producing the substances in sufficient quantities for commercial use.
• GM plants for producing active pharmaceutical ingredients (molecular pharming, PMP = plant-made pharmaceuticals)
  According to the TAB report, it is “surprising” that pharmaplants appear to be more advanced than other fields of application. Although no GM plants for the production of active pharmaceutical ingredients have yet been licensed, even in Europe intensive research and deliberate release trials can be observed. Fifteen pharmaceutical substances produced by plants are currently at various stages of clinical testing. However, early indications are that using plants as a production platform does not have any cost advantages over other forms of production.

Safety issues: New challenges. If the next generation of GM plants are actually used, in many cases it will be necessary to organise the cultivation of these plants so as to ensure their total separation from the food and animal feed chain.

In principle there are two approaches for sealing off these GM plants from the environment:

• Physical measures, for example greenhouses, spatial separation of fields (containment)
• Biological measures, e.g. using plant species which are not used in agriculture or sterile plants as production platforms (confinement)

To a certain and relatively large extent, it is possible to limit the spread of transgenic plants or their genetically produced characteristics with biological and physical measures. However, according to the TAB report, “On the basis of existing scientific knowledge and technology, containment and confinement of transgenic useful plants cannot provide a system, which will allow GM and non-GM crop varieties grown outdoors to exist alongside one another whilst completely excluding all interference. What degree of interference under what conditions will be tolerated remains a question for society to address.”