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To: Anthony Wong who wrote (1818)	3/25/1999 3:45:00 PM
From: Anthony Wong	Respond to of 2539

Better test for GM foods BBC Thursday, March 25, 1999 Published at 16:44 GMT A UK company has developed a highly-sensitive technique for testing whether foods contain genetically-modified ingredients. RHM Technology, based in High Wycombe, believes its new test is far more sensitive than any other method currently in use. As the row over GM food has intensified, the issue of testing has become an important one. Ethical, health and environmental concerns have led many groups to demand better labelling on foodstuffs. This requires a precise way of detecting and measuring the chemicals signatures left in products by the processes of gene modification. This has proved difficult. In a standard test, a sample is scrutinised for stretches of DNA that come from genes that do not occur naturally in the foodstuff. Processed food Although, detecting genetic modifications in raw or lightly processed food is straightforward. It becomes more problematic when testing highly processed foods. Processing and cooking can destroy the sections of DNA being sought. It also creates numerous types of small molecules that can interfere with the reaction used to amplify the sample for analysis. This can lead to false negative and occasionally false positive results. The new test from RHM Technology claims to overcome these difficulties. It looks for smaller fragments of DNA which are more likely to survive processing. Special resin Confusion caused by small molecules is reduced after the sample is purified and washed in a special resin. RHM Technology says it can also estimate the percentage of the ingredients that are genetically modified. "That is an important leap forward," Bob Marsh, the company's managing director, told the BBC. The new test will be welcomed as the European Union is currently considering its position on the threshold levels used to determine whether foods need to carry a GM label. New thresholds It is expected to introduce rules that would allow food to be labelled as GM-free if they contained soya or maize that had less than about 2% GM ingredients. This will prevent companies being blamed for accidental contamination. RHM Technology is owned by Ranks Hovis McDougall, but it will be making the test available to its rivals in the food industry. "This test will enable the establishment of thresholds," Bob Marsh said. "We are able to take in samples for testing from other groups because we are not competitive on testing - RHM is just competitive in the way it manufactures its food products." The new test is featured in New Scientist Magazine. news.bbc.co.uk

To: Anthony Wong who wrote (1818)	3/25/1999 3:49:00 PM
From: Anthony Wong	Respond to of 2539

Freeze! Gene police! From New Scientist, 27 March 1999 Andy Coghlan A TEST LAUNCHED THIS WEEK should give teeth to the European Union's strict labelling rules on genetically engineered foods. It detects minute traces of genetically modified soya and maize even in highly processed products, a feat considered impossible until now. From September last year, retailers in the EU have had to label products containing GM soya or maize. Britain extended this requirement last week to include menus in restaurants and cafés. But critics complain that the lack of an effective test makes the rules meaningless. Even Jeff Rooker, Britain's food minister, has conceded that it is not possible to check the GM content of highly processed food products. RHM Technology of High Wycombe, Buckinghamshire, says it now has a test that detects traces of GM ingredients even in heavily processed products, such as those containing soya oil or lecithins. RHM developed the test to allow its parent company, Ranks Hovis McDougall, to monitor the GM content of its own products, which include cakes, sauces, bread and jams. The company will also be able to see if its rivals are failing to label products containing GM ingredients. "We've even found some contaminated items in health food stores," says Bob Marsh, managing director of RHM Technology. The test is also the first to measure accurately what percentage of an ingredient is genetically engineered, claims Marsh. That could be important for food inspection agencies. The EU is expected to introduce rules which allow food to be labelled GM-free if less than, say, 2 per cent of the soya or maize within the product is genetically eng-ineered. This will prevent companies being penalised for accidental contamination. The test registered the correct level of contamination in a loaf deliberately spiked with GM soya flour, says Gordon Wiseman, head of the team that developed it. Soya accounted for 0.67 per cent of the weight of the test loaf, and just 2 per cent of this fraction had been genetically engineered. Like other tests for GM foods, RHM 's detects DNA sequences unique to the transgenic ingredient. These include the cauliflower mosaic virus promoter, the "switch" for activating added genes. To generate the millions of copies needed for detection and analysis, the DNA fragments in a sample must be multiplied using the polymerase chain reaction (PCR). But food processing degrades DNA. Another problem is that substances in processed food, such as salt, calcium and polysaccharides, block PCR. To overcome these obstacles, Wiseman's team has designed the test to recognise much smaller fragments of the same genes, which survive processing. The PCR-blocking substances are removed by purifying the DNA with a specialised resin produced by Promega of Madison, Wisconsin. To establish what percentage of the ingredient is transgenic, Wiseman measures the content of two genes from each sample. One is unique to the genetically engineered ingredient, and one occurs in the transgenic and the natural material. In tests for GM soya, he compares the amount of cauliflower mosaic virus promoter with the amount of the natural soya lectin gene. Wiseman uses specialised fluorescent probes to monitor accumulation of these gene replicas at each successive cycle of PCR. By comparing the intensity of the glow of the probes for the natural and transgenic sequences, he can calculate the percentage of soya or maize that is genetically engineered. newscientist.com