Genetic code of rice cracked

LONDON, JAN. 27. The entire genetic formula for rice has been unravelled by scientists.

The completion of the ``rice genome map'', announced on Friday by the Torrey Mesa Research Institute, part of the company Syngenta, and Myriad Genetics Inc. in America, is the first project of its kind in a crop plant.

Because rice - which is the staple food for more than half the world's population - is a model for other cereals, the breakthrough will accelerate the development of genetically modified crops. It will also add fuel to the debate over GM foods and whether First World fears have obscured the technology's benefits for the Third World.

Rice plants have approximately 50,000 different genes, which are written in about 430 million ``letters'' of DNA, so the achievement marks the second largest genome to be sequenced to date, after that of humans.

The information will be used by plant breeders to select the best progeny from creating cross-varieties of rice within five years, while biotechnologists will use it to identify and transfer individual genes from one rice variety to another so that GM rice can be made within about seven years.

Because of the similarity between different cereal crop plants, the work will contribute to the study of other important cereals such as wheat, corn, and barley, and lead to new varieties.

Dr. Steve Briggs, president of TMRI, said: ``We are very proud that our institute has pioneered this research. Identifying not only the genes, but their functions and how they work, will provide researchers with crucial new knowledge to improve food crops.''

Rice has been grown as food for more than 5,000 years and is consumed by three billion people each day. Rice growing uses large volumes of water and, compared with similar crops, are inefficient. It is also vulnerable to drought.

The dependency of so many people on rice as their staple food makes it crucial that production does not falter.

The introduction of new rice varieties over the past 30 years has succeeded in doubling production. However, in Asia alone, the demand for rice is expected to increase by 70 per cent over the next 30 years.

Current methods of plant breeding will only be able to increase rice production to meet part of this demand, as land, labour and water become significant limiting factors.

Scientists believe that knowing the rice genome will aid efforts to improve yields and increase the crop's resilience.

Dr. David Evans, head of research and technology at Syngenta, said: ``Understanding cereal genetic structure and associated proteins will enable plant breeders to produce crops that are more nutritious, more productive and easier to process. We will also research new ways to protect crops from diseases or pests, and discover new uses for crop plants. This offers exciting new opportunities to improve agricultural yields and quality.''

Syngenta said it would work with research institutes in the developing world to explore how its research can best be used to improve crops and benefit subsistence farmers.

A spokesman said: ``It is our policy to provide such information and technology for use in products for subsistence farmers, without royalties or technology fees.''

One example of the type of benefits that the research will bring is the development of a genetically modified golden rice variety that is rich in vitamin A.

About 124 million children do not get enough vitamin A in their diets and it is a leading cause of blindness. It also causes up to a million deaths a year in developing countries.

Prof. Ingo Potrykus of the Swiss Federal Institute of Technology has added three genes to rice plants, two from the daffodil and one from a bacterium, to produce rice plants that make enough beta-carotene - converted to vitamin A by the body - to meet the total vitamin A requirement through a typical Asian diet.

The rice genome sequence is the most accurate and comprehensive large genome with direct commercial value to be sequenced so far.

The rice genome map is better than 99.5 per cent complete, compared with the human genome map, which still contains a number of large gaps and is estimated to be approximately 90 to 95 per cent complete.

A public consortium, the International Rice Genome Sequencing Project, aims to produce a more detailed genetic sequence by 2005. - FTelegraph Group Limited, London, 2001

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