Rapid Responses to:
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Rapid Responses: Rapid Responses published:
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GM foods and the Pusztai affair
- Jonathan M Rhodes (5 March 1999)
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Informing patients if drugs contain genetically modified substances?
- Venkat Raghavan (22 April 1999)
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Declaring Competing Interests
- J T Winkler (17 June 1999)
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Re: Declaring Competing Interests
- Leighton Jones (3 September 2001)
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Jonathan M Rhodes
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Editor, In the Clinical Review by Leighton Jones (1) it is implied that Dr Pusztai's experiments had only tested the effects of potato spiked with ConA lectin. It was the initial dissemination of this incorrect information followed by the inappropriate suspension of Dr Pusztai and the implied fraud that was suggested by the institution of an audit according to MRC guidelines that led myself and other scientists to allow our names to be included in the memorandum defending Dr Pusztai, whom we know to be an honourable and careful scientist. It is clear from the report of the Audit conducted at the Rowett Institute in August 1998, and so far only incompletely released (http://www.rri.sari.ac.uk/press), that experiments involving transgenic potatoes containing the gene for the snowdrop lectin (GNA) had already been performed at the time of Dr Pusztai's World in Action television interview. If the Rowett Institute had simply released a statement that the work was preliminary and allowed the work to continue it is unlikely that such a potentially damaging media storm would have resulted. There has been little clarity surrounding the subsequent media debate and this situation has unfortunately been exacerbated by some misleading statements from fellow scientists. Firstly: not all lectins are toxic. They are ubiquitous carbohydrate-binding proteins. All mammalian cells and blood and all plant nuts, seeds and bulbs, including many non-toxic food components contain lectins (2). Some of these, red kidney bean lectins for example, are toxic and need to be destroyed by heat before consumption but others such as tomato lectin are apparently harmless when eaten raw. Some of these food lectins have very interesting biological effects - our group has recently reported the selective inhibition of nuclear-localising-sequence-dependent nuclear protein import by the common edible mushroom lectin which we often eat raw (3). Many of these plant lectins serve an insecticidal or antifungal role in the plant. The snowdrop lectin (GNA) binds to mannose which is minimally expressed in mammalian intestine but extensively expressed in the intestine of sap-sucking insects. It is therefore plausible that expression of this lectin in food plants might render them unattractive to insects but safe for human consumption, particularly if the food (potato) is always cooked before ingestion. Secondly: the experiments performed by Dr Pusztai, whatever their results, would not imply that all genetically modified foods were unsafe. The message which Dr Pusztai was trying to put across was simply that such foods require very careful testing. As with the testing of new pharmaceuticals, some such transgenic foods will prove toxic or otherwise unsatisfactory and be discarded at an early stage of development. Thirdly: the fact that Dr Pusztai has been barred from continuing his experiments since the time of his initial suspension has resulted in a very unsatisfactory situation in which his data although interesting remain preliminary and further experimentation will probably need to be done before any final conclusions can be drawn about the effects of the transgenic GNA potato or its promoter. One lesson to be learnt from this episode is that all scientists need to be careful to ensure that their comments serve to inform rather than confuse when handling issues that carry such extreme public interest. Jonathan M Rhodes Professor of Medicine, University of Liverpool, rhodesjm@liverpool.ac.uk, tel 0151 706 4073, fax 0151 706 5802 1. Jones L. Genetically modified foods. Science, medicine, and the future. Clinical Review. British Medical Journal 1999, 318:581-84. 2. Rhodes JM. Beans means lectins. Commentary. Gut 1999 in press. 3. Yu L-G, Fernig DG, White MRH, Spiller DG, Appleton P, Evans RC, Grierson I, Smith JA, Davies H, Gerasimenko OV, Petersen OH, Milton JD, Rhodes JM Edible mushroom (Agaricus bisporus) lectin, which reversibly inhibits epithelial cell proliferation, blocks Nuclear Localization Sequence-dependent nuclear protein import. J Biol Chem 1999; 274: 4890-99. |
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Venkat Raghavan
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Editor-- We read with interest your recent editorial and clinical review on genetically modified foods 1. One such substance which appears to commonly come from a genetically modified source is soya bean oil and since there is a move towards the labelling of such substances in order that the public are made aware if they are consuming genetically modified products, this immediately caught our attention . In the field of anaesthesia one of the most commonly used intravenous induction agent is Propofol. It is also widely used for sedation in Intensive Care Units. This drug is presented as an emulsion with soya bean oil as one of the ingredients of the vehicle solution. Propofol is one of the number of drugs in daily use in anaesthesia and other fields of medicine which may contain genetically modified ingredients. It has occurred to us that, in line with the Government policy on the labelling of genetically modified foods, perhaps we should be informing patients if any of the drugs they are to receive contain genetically modified substances. Is it now the responsibility of the manufacturers to declare the presence of genetically modified substances in their products or to declare them free of genetic modification if this is the case? Venkat Raghavan, Senior House Officer in Anaesthetics Christina Wood, Specialist Registrar in Anaesthetics Mayday University Hospital, Thornton Heath, Surrey CR7 7YE 1 Leighton Jones. Genetically Modified Foods BMJ 1999;318:581-584 (27 February) |
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J T Winkler, Director, Food & Health Research 28 St Paul Street, London N1 7AB
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Leighton Jones of Campden & Chorleywood Food Research Association has failed to declare competing interests in connection with his article on genetically modified foods. C&C is a membership organisation. Most of its fee-paying members are major food companies. Many of these companies are producing, researching or considering GM products. C&C provides multiple services, including contract research, for these companies, either collectively or individually, in return for fees. Therefore, for an employee of C&C to asssert that he has no competing interests in this field is not true. These financial connections may or may not influence what he writes. But when the BMJ asks a direct question about such interests, he should declare them. The BMJ has led the way in setting demanding standards to uncover falsified research results. You should have equally high standards to uncover undeclared conflicts of |
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Leighton Jones
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With regard to the comments on competing interests, submitted by JT Winkler, I wish to make two observations. First, in seeking information on competing interests, the BMJ asks not one but a whole series of direct questions. I completed the questionnaire truthfully and honestly. The final section of the questionnaire asks the author to assert that they have no competing interests (which leads to publication of 'Competing interests: None declared' on the article) or to provide a statement briefly stating any interests. I chose the latter (I did not tick the box asserting I had no competing interests). However, for some reason, the BMJ published both the 'None declared' and the statement I provided. Second, 'food' companies do not hold a consolidated view on GM foods. Some (e.g. biotech companies) are obviously highly pro-GM technology while others (e.g. the retailer Iceland) have been publicly anti-GM foods. The purpose of the article (which I was invited to write - I have no drum to beat) was to present the information as factually as possibly - and to consider isues case-by-case. This I tried to do. I hope this statement clarifies my position. |
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