Louise a écrit:
Sandra : oui il était question de tests sur des rats ayant consommé des produits OGM et des dommages et malformations de leur organisme...
Je suis assez surpris de lire ça. Il n'y a pour le moment pas d'étude sérieuse qui montre de tels résultats. Je ne parle pas d'études menées par les producteurs des semences mais bien d'études réalisées par des laboratoires public ...
J'ai trouvé par exemple celui-ci :
Le gene bar dont il est question ici est un gène de résistance à un hebicide qui provient de streptomyces hygroscopicus (bactérie anaérobie du sol)
Multigeneration Reproductive and Developmental Toxicity Study of bar Gene Inserted into Genetically Modified Potato on Rats
Authors: Seek Rhee, Gyu1; Hyun Cho, Dae1; Hyuck Won, Yong1; Hyun Seok, Ji2; Sun Kim, Soon1; Jun Kwack, Seung2; Da Lee, Rhee1; Yeong Chae, Soo1; Woo Kim, Jae1; Mu Lee, Byung3; Lea Park, Kui1; Sik Choi, Kwang2
Source: Journal of Toxicology and Environmental Health Part A, Volume 68, Numbers 23-24, Number 23-24/December 10 2005 , pp. 2263-2276(14)
Abstract:
Each specific protein has an individual gene encoding it, and a foreign gene introduced to a plant can be used to synthesize a new protein. The identification of potential reproductive and developmental toxicity from novel proteins produced by genetically modified (GM) crops is a difficult task. A science-based risk assessment is needed in order to use GM crops as a conventional foodstuff. In this study, the specific characteristics of GM food and low-level chronic exposure were examined using a five-generation animal study. In each generation, rats were fed a solid pellet containing 5% GM potato and non-GM potato for 10 wk prior to mating in order to assess the potential reproductive and developmental toxic effects. In the multigeneration animal study, there were no GM potato-related changes in body weight, food consumption, reproductive performance, and organ weight. Polymerase chain reaction (PCR) was carried out using extracted genomic DNA to examine the possibility of gene persistence in the organ tissues after a long-term exposure to low levels of GM feed. In each generation, the gene responsible for bar was not found in any of the reproductive organs of the GM potato-treated male and female rats, and the litter-related indexes did not show any genetically modified organism (GMO)-related changes. T
he results suggest that genetically modified crops have no adverse effects on the multigeneration reproductive–developmental ability. Ces résultats montrent que les semences génétiquement modifiées n'ont pas d'effets négatif la capacité de reproduction des rats étudiés
Affiliations: 1: Department of Toxicology, National Institute of Toxicological Research, Korea Food and Drug Administration, Seoul 2: Department of Risk Analysis, National Institute of Toxicological Research, Korea Food and Drug Administration, Seoul, Korea 3: Division of Toxicology, School of Pharmacy, Sungkyunkwan University, Changan-Ku, Kyunggi-Do, Suwon
Ou encore celui-ci :
[Study on food safety of genetically modified rice which expressed cowpea trypsin inhibitor by 90 day feeding test on rats]
Zhuo Q, Chen X, Piao J, Gu L.
Institute of Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
OBJECTIVE: Rats were fed by transgenic rice which expressed insecticidal protein CPTI (cowpea trypsin inhibitor) to study if the transgenic rice possessed potential toxic or adverse effects. METHODS: Weanling Wistar rats were randomly divided into three groups: T, N and C group. The diet of T group contained 78.3% transgenic rice. The diet of N group contained 74.7% non transgenic rice which was the parent line of the transgenic one. The diet formula of C group was AIN93G. The macro- and micronutrient content were equal in three diets. The rats were fed for 90 days. Food intakes were weight every day, body-weight were weight and body-length were measured every week. In the middle and at the end of feeding period, haematological value and clinical chemistry parameters were measured, at the end of the 90th day, post-mortem organ coefficient were measured, organ tissues analysis was performed and bone density was measured. RESULTS: In most situation, there were no significant differences among the three groups(P > 0.05) and no histopathological damage were detected. At the end of the 1st month, the male rats' body length of the T group was longer than the other two groups and at the end of the test period, the male rats' blood glucose and ALT were lower than the other two groups. In the middle of the test period, the female rats' red blood cell number and hemoglobin were higher than the other two groups and at the end of the test period, the female rats' monocyte number was higher than the other two groups (P < 0.05). But all of the results were in the normal range which had been reported before. CONCLUSION:
From the results of the 90 days feeding test of transgenic rice on rats there did not reveal any signs of toxic and adverse effects. 90 jours de consommation de riz transgénique ne montre aucun signe de toxicité (90 jours c'est court !)
Wei Sheng Yan Jiu. 2004 Mar;33(2):176-9.
Celui-ci assez intéressant sur les malformations foetales :
Study on the teratogenicity effects of genetically modified rich which expressed cowpea trypsin inhibitor on rats]
Zhuo Q, Chen X, Piao J, Han C.
Institute of Nutrition and Food Safety, Chinese Centre for Diease Control and Prevention, Beijing 100050, China.
OBJECTIVE: Rats were fed by transgenic rice which expressed insecticidal protein CpTI (cowpea trypsin inhibitor) to study if the transgenic rice possessed potential teratogenicity effects. METHODS: Weanling Wistar rats were randomly divided into four groups: transgenic rice group, non transgenic rice group, negative control group and positive control group. The diet of transgenic rice group contained 78.3% transgenic rice. The diet of non transgenic rice group contained 74.7% non transgenic rice which was the parent line of the transgenic one. The diet formula of the two control groups was AIN93G. The marco- and micronutrient content were equal in three diets. When the sexual maturation period of rats arrived, conventional teratogenicity test was performed. RESULTS: The body weight gain of pregnant rats and body weight, body length and tail length of fetal rats in transgenic rice group were significant higher than those in positive control group (P < 0.01).
The malformation rate of fetus in transgenic rice group was significant lower than that in positive control group (P < 0.01). CONCLUSION: There were no significant differences of all indexes among transgenic rice group, non transgenic rice group and negative control group (P > 0.05). Judging from these results, the transgenic rice modified with CpTI was considered to have no maternal toxicity, embryotoxicity and teratogenicity effects. Le taux de malformation foetale est significativement plus faible dans le groupe de rats nourris avec des OGM pas rapport au groupe nourrit sans OGM. Pas de toxicité maternelle, pas de toxicité embryonnaire et pas de teratotoxicité (qui provoque des malformation)
Wei Sheng Yan Jiu. 2004 Jan;33(1):74-7.
Par contre une équipe française a montré que bien que n'ayant pas d'effet toxique sur les abeilles, la protéine CpTI à forte concentration a néamoins un effet sur leur comprtement et leur capacité d'apprentissage
Impact of proteins used in plant genetic engineering : Toxicity and behavioral study in the honeybee
Auteur(s) / Author(s)
PICARD-NIZOU A. L. (1) ; GRISON R. (1) ; OLSEN L. (1) ; PIOCHE C. (1) ; ARNOLD G. (1) ; PHAM-DELEGUE M. H. (1) ;
Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)
(1) Laboratoire de Neurobiologie Comparée des Invertébrés, INRA-CNRS (URA 1190), BP 23, 91440 Bures-sur-Yvette, FRANCE
Résumé / Abstract
Genetically modified oilseed rape, Brassica napus L., expressing pest and fungi resistance has been assessed for its impact on the environment before field testing and placing on the market. The evaluation of rape lines for their inocuousness to beneficial insects such as the honeybee, Apis mellifera L., were investigated because changes in the composition of nectar and pollen may occur that affect plant- honeybee interactions. The effects of these plants on bees were evaluated by acute toxicity testing of the gene products and behavioral studies of bees. Acute toxicity was determined by evaluating the mortality over 24- and 48-h periods after ingestion or injection of the gene products. For the bee behavioral study, methods used to study learning processes and foraging behavior were adapted to test the effect of the gene products at both individual and colony levels under confined conditions. The study focused on the effects of proteins inducing resistance to pest insects, cowpea trypsin inhibitor (CpTI), and resistance to fungi, chitinase, and β-1,3 glucanase. Under our experimental conditions, the 3 proteins were shown to be nontoxic at the doses tested. At the individual level, behavior experiments, based on a conditioned proboscis extension response, had the following 3 effects depending on the protein tested; (1) chitinase did not affect learning performance; (2) β-1,3 glucanase affected the level of conditioned responses, with the extinction process occurring more rapidly as the concentration increased; and (3) CpTI induced marked effects in both conditioning and testing phases, especially in high concentrations. The decrease in learning performance induced by CpTI observed at the individual level was confirmed at the colony level. Given their relative simplicity, it is suggested that such bioassays could be used for screening in the development of genetically modified plants.
Revue / Journal Title
Journal of economic entomology (J. econ. entomol.) ISSN 0022-0493 CODEN JEENAI
Source / Source
1997, vol. 90, no6, pp. 1710-1716 (22 ref.)
Pour finir, il y a cette revue parue en 2007 qui montre clairement et objectivement le problème des OGM : Il y a très peu d'étude et on ne sait rien. On a très peu de recul et pas suffisamment de données. Il n'y a pas de toxicité avérée et démontrée des OGM, de même que leur inocuité ne peut non plus pas être affirmée. Qu'ils soient pour ou contre les OGMs, tous ceux qui prétendent avoir la réponse sont des menteurs et ne font font référence qu'a quelques cas particuliers. La seule vérité est que pour le moment on ne sais pas ! C'est d'autant plu vrai que ce n'est pas la "technique OGM" en elle même qui est potentiellement dangereuse pour la santé mais le gène/protéine qui est "implanté" et qui dépend de la fonction de cette protéine.
En France, on a choisi d'appliquer le principe de précaution, et c'est tant mieux pour nous. Il est regrettable que ça ne soit pas le cas dans tous les pays.
Je n'ai pas sélectionné quelques articles montrant ce que je souhaitais montrer. J'ai réellement passé plus d'une heure à rechercher des articles de façon objective. Je n'en ai pas trouvé un seul apportant la preuve que des malformations pouvaient être induite par la consommation de produits OGMs. Si quelqu'un a une référence, je voudrais bien la récupérer pour lire les articles en question.
[color=red]De toute façon tous les biologistes moléculaires, généticiens et biochimistes vont être excommuniés car le Vatican viens de décréter que toute manipulation génétique constituait un péché capital :shock:
[/color]
Toxicity Studies of Genetically Modified Plants: A Review of the Published Literature
Author: José L. Domingo a
Affiliation: a Laboratory of Toxicology and Environmental Health, School of Medicine, "Rovira I Virgili" University, San Lorenzo, Reus, Spain
Published in: journal Critical Reviews in Food Science and Nutrition, Volume 47, Issue 8 November 2007 , pages 721 - 733
Abstract
According to the information reported by the WHO, the genetically modified (GM) products that are currently on the international market have all passed risk assessments conducted by national authorities. These assessments have not indicated any risk to human health. In spite of this clear statement, it is quite amazing to note that the review articles published in international scientific journals during the current decade did not find, or the number was particularly small, references concerning human and animal toxicological/health risks studies on GM foods. In this paper, the scientific information concerning the potential toxicity of GM/transgenic plants using the Medline database is reviewed. Studies about the safety of the potential use of potatoes, corn, soybeans, rice, cucumber, tomatoes, sweet pepper, peas, and canola plants for food and feed were included.
The number of references was surprisingly limited. Moreover, most published studies were not performed by the biotechnology companies that produce these products. This review can be concluded raising the following question: where is the scientific evidence showing that GM plants/food are toxicologically safe? Ou est la preuve scientifque que les OGM sont sans danger
Keywords: genetically modified (GM) plants; toxicity; safety; health risks; DNA
J'ai effectivement était très surpris de voir qu'il a a si peu d'articles qui sortent sur le sujet quand on interroge les bases de données.
Et c'est effectivement inquiétant...
Benoît
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Et c'est vrai que nous en consommons sanS le savoir, car ce n'est pas toujours indiqué 
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