An inconvenient truth being ignored by GM wheat protesters Take the Flour Back

(Originally Posted at GMO Pundit Blog)

Protest organisation Take the Flour Back (TTFB) and and others who support them are basing some of their claims about lack of safety of genetically modified food on a particular study by Canadian workers which claims to detect insect protection protein known as Bt in blood fluids of pregnant women and in human foetuses.
Maternal and fetal exposure to pesticides associated to genetically modified foods in Eastern Townships of Quebec

The same protein Bt is present in many genetically modified insect protected plants such as Bt corn.
Claims about this protein entering the human body are made by TTFB in promotional videos present on the protest website for instance, and have been recently been reported in British newspapers by food writers sympathetic to the claims of TTFB.
The information is spurious.
The scientists reporting finding Bt protein in the human samples (Aris and Leblanc)  are detecting only noise in the assay system because they use an invalid assay system (Agdia) intended to test plants, not animals for Bt.

The inconvenient truth about this is described in an earlier paper Paul and others 2007  that demonstrates how to do a valid assay for this Bt protein and also shows what kind of results you get from a valid test with animal samples.
The basic message is that:  no detectable Bt protein in GM food enters an animal body from the gut.
Aris and Leblanc 2011 are not aware of this paper by Paul and others as they fail cite it  in their reference list but they should because it was published years earlier than their report. They use a commercial assay (Agdia) that is intended for use with plant material on human tissue samples. Paul and others publication shows this is a faulty analysis procedure.

Here is the inconvenient truth quoted from the paper by Paul that’s ignored by both TTFB and Aris and Leblanc:
Development and validation of a sensitive enzyme immunoassay for surveillance of Cry1Ab toxin in bovine blood plasma of cows fed Bt-maize (MON810)

SUMMARY
The increasing global adoption of genetically modified (GM) plant derivatives in animal feed has provoked a strong demand for an appropriate detection method to evaluate the existence of transgenic protein in animal tissues and animal by-products derived from GM plant fed animals. A highly specific and sensitive sandwich enzyme immunoassay for the surveillance of transgenic Cry1Ab protein from Bt-maize in the blood plasma of cows fed on Bt-maize was developed and validated according to the criteria of EU-Decision 2002/657/EC.
The sandwich assay is based on immuno-affinity purified polyclonal antibody raised against Cry1Ab protein in rabbits. Native and biotinylated forms of this antibody served as capture antibody and detection antibody for the ELISA, respectively. Streptavidin-horseradish peroxidase conjugate and TMB substrate provided the means for enzymatic colour development.
The immunoassay allowed Cry1Ab protein determination in bovine blood plasma in an analytical range of 0.4–100 ngmL-1 with a decision limit (CCalpha) of 1.5 ngmL-1 and detection capability (CCbeta) of 2.3 ngmL-1. Recoveries ranged from 89 to 106% (mean value of 98%) in spiked plasma.
In total, 20 plasma samples from cows (n = 7) fed non-transgenic maize and 24 samples from cows (n = 8) fed transgenic maize (collected before and, after 1 and 2 months of feeding) were investigated for the presence of the Cry1Ab protein. There was no difference amongst both groups (all the samples were below 1.5 ngmL-1; CCalpha). No plasma sample was positive for the presence of the Cry1Ab protein at CCalpha and CCbeta of the assay.
FROM THE INTRODUCTIONA number of ELISA [21–25] and commercial kits (QuantiPlate kit for Cry1Ab/Cry1Ac, Envirologix and DAS ELISA kit for Bt-Cry1Ab/1Ac protein, Agdia) are already existing for the detection and quantification of Cry1Ab protein expressed in GM crops and their by-products. These commercial kits have been also used in various livestock feeding studies on GMO for the surveillance of transgenic protein in the animal tissues and gastrointestinal contents [17–20,26].
Though the commercially available Cry1Ab protein ELISA kits (QuantiPlate kit for bCry1Ab/Cry1Ac, Envirologix and Agdia)were reported to detect Cry1Ab protein down to 1ngmL-1 of spiked blood [26], however, the study missed the most important assay validation part. Further, in another study [19] the same ELISA kit (Envirologix) did not work for the analysis of blood plasma for the surveillance of transgenic protein. Hence, such commercial kits designed for transgenic protein (Cry1Ab or Cry1Ac) quantification in plant materials warrants for a proper assay validation before used for protein analysis in animal systems.Therefore, an assay for the specific detection, including all validation criteria, is required, in particular for the monitoring of transgenic protein in animal products (like blood plasma, milk and meat) derived form GM plant fed animals.
The aim of the present study was: (a) to raise and purify the Cry1Ab toxin specific polyclonal antibody for the development of a sensitive, specific sandwich ELISA for the surveillance of Cry1Ab protein in blood plasma of cows receiving ration supplemented with Bt-maize (MON810) and (b) to validate of this assay as per the requirements of assay validation cited in the guidelines of EU-Decision 2002/657/EC[27]
RESULTS3.4. Application of developed ELISA for the surveillance of Bt-toxin in blood plasma of cows fed transgenic maize (MON810)
In total 45 blood plasma samples (collected before and, after 1 and 2 months of feeding) were analyzed for the presence of the Cry1Ab protein from both, transgenic (n = 8) and non-transgenic (n = 7) ration fed cows. There was no difference amongst both groups (all plasma samples were below 1.5 ngmL-1; CCalpha value). No sample was positive for the presence of the Cry1Ab protein at the decision limit (CCalpha) and detection capability (CCbeta) of the assay (Fig. 5). The absence of transgenic (Cry1Ab) protein from Bt-maize in blood plasma of cows is supported by the other findings reporting the lack of transgenic protein in the tissues (liver, spleen, kidney, lymph nodes and muscles) from livestock that had consumed GM corn [18,19,29]. The reasons for the absence of the Cry1Ab protein from Bt-maize in the blood plasma of cows fed transgenic ration could be the lack of the absorption mechanism involved in the transfer of this toxin from the gut into the blood stream. This could be further supported by the findings reporting the lack of Cry1Ab toxin specific receptors on bovine intestinal epithelium [13,14] and in vivo degradation of trans-genic protein during ruminal digestion [17]. The absence of novel protein in blood plasma of cows fed Bt-maize may consider it as a safe animal feed. The previous findings [16] of a short-term Bt11 maize feeding study on calves demonstrating no negative effects on development of any discernible clinical symptoms, growth rate, hematology, blood biochemistry, and rumen functions further supports Bt-maize as a safe animal feed. In addition the animal performance studies on lactating cows fed GM corn has depicted no changes in animal health, behavior, milk yield and milk composition in comparison to non-GM corn fed cows [30–32]. Though the short-term feeding studies consider GM corn as a safe animal feed, however, before drawing any definitive conclusions a long-term feeding study is warranted.
…This is, to our knowledge, the first immunoassay for a specific detection of Cry1Ab toxin in the blood plasma of cows fed transgenic maize. The assay also fulfills all the validation criteria as prescribed in the guidelines of EU-Decision 2002/657/EC.Though the commercially available Cry1Ab protein ELISA kits (QuantiPlate kit for Cry1Ab/Cry1Ac, Envirologix and Agdia) were reported to detect Cry1Ab protein down to 1ngmL-1 of spiked blood [26], however, the study missed the most important assay validation part. Further, in another study [19] the same ELISA kit (Envirologix) did not work for the analysis of blood plasma for the surveillance of transgenic protein…
Vijay Paul a,., Kerstin Steinke a,b, Heinrich H.D. Meyer a
a Physiology Weihenstephan, Technical University Munich, Weihenstephaner Berg 3,
85350 Freising, Germany
b Bavarian State Research Center for Agriculture, Institute for Animal Nutrition and Feed Management,Prof.-Duerrwaechter-Platz 3, 85586 Poing, Germany
Analytica Chimica Acta 6 0 7 ( 2 0 0 8 ) 106–113

See also earlier GMO Pundit Posts

See next GMO Pundit post False claims for the nitty-gritty detail about Aris and Leblanc’s errors.
David Tribe

Written by David Tribe

David Tribe’s research career in academia and industry has covered molecular genetics, biochemistry, microbial evolution and biotechnology. He has over 60 publications and patents. Dr. Tribe's recent activities focus on agricultural policy and food risk management. He teaches graduate programs in food science and risk management as a Senior Lecturer in the Department of Agriculture and Food Systems, University of Melbourne.

58 comments

  1. I love it when n = a smiley face wearing dark glasses – thats when you know you have a statistically sound trial.

  2. If all in favour of any dodgy science – on any side – being exposed. The blog did not explain how the flawed method would have given that result. It made me wonder. I would therefor ask the author to make clear whether the flawed methodology would have been responsible.

  3. Maine’s organic propaganda outlet, Maine Organic Farmers and Gardeners Association, cited the Aris and Leblanc article in an editorial designed to scare consumers off “conventional” produce:

    …the OTA cites a study by Quebec scientists who found the Bt toxin in 93 percent of maternal and 80 percent of fetal blood samples, and in the blood of 69 percent of non-pregnant women tested.

    http://mofga.org/Publications/MaineOrganicFarmerGardener/Spring2012/EnglishEditorial/tabid/2149/Default.aspx
    This spurred me to actually read a scientific paper, something I’m not in the habit of doing. Luckily, I have a friend in bio-tech who can help me make sense of things.
    I found that the authors undermine their claims when they admit that they do not even know the sources of the Bt toxin they have allegedly detected. They ask us to just assume it is from Bt corn. This is stated in (literally) fine print:

    Our study did not quantify the exact levels of [pesticides-associated genetically modified foods] in a market-basket study. However, given the widespread use of GM foods in the local daily diet … it is conceivable that the majority of the population is exposed through their daily diet.

    In plain English, the authors have made no attempt to determine whether the women tested ate Bt corn,let alone in the quantities necessary to permit detection of the toxin in blood.
    This is beyond scandalous.

  4. I forgot to say: I wrote a nice 500-word rebuttal of the editorial cited above, including a citation of Dr. Tribe’s work exposing the Aris and Leblanc paper, and I didn’t hear a damn thing back from MOFGA.

  5. Not sure why you’re having trouble following along Orphadeus….

    Further, in another study [19] the same ELISA kit (Envirologix) did not work for the analysis of blood plasma for the surveillance of transgenic protein. Hence, such commercial kits designed for transgenic protein (Cry1Ab or Cry1Ac) quantification in plant materials warrants for a proper assay validation before used for protein analysis in animal systems.Therefore, an assay for the specific detection, including all validation criteria, is required, in particular for the monitoring of transgenic protein in animal products (like blood plasma, milk and meat) derived form GM plant fed animals.

    Your friends A&L failed to follow along too, hence, their data, results, and conclusions are meaningless.

  6. Chuckle. The Smiley face is some weird font artifact of the n=8 , n equals 8 written text, but I’ll let it stand for the wonderous accidental humour.

  7. As to an explanation for false signal, it could be caused by weak low-level non-specific binding of serum proteins to the sample serum proteins that exploited as detection reagents in the test. In the body, various different interactions occurs between proteins because of their normal role in physiology and defence, and the assay can non-intentionally respond to these chemical interactions.
    When the cops stop you and breath test you, and you’ve been sucking certain cough-candies, it can give a false alcohol signal. It’s like that.

  8. yeah it’s 8) because why would anyone ever want to put a close paren after an 8!

  9. The basic message is that: no detectable Bt protein in GM food enters an animal body from the gut.

    What about sublingually?

  10. ‘Further, in another study [19] the same ELISA kit (Envirologix) did not work for the analysis of blood plasma for the surveillance of transgenic protein.’
    19 is:
    Detection of Corn Intrinsic And Recombinant DNA Fragments And Cry1Ab protein In The Gastrointestinal Contents Of Pigs Fed Genetically Modified Corn Bt11
    That is here:
    http://www.somloquesembrem.org/img_editor/file/detecciopanisBt11tocinosChowdury.pdf
    It states:
    ‘These results suggest that ingested corn DNA and Cry1Ab protein were not totally degraded in the gastrointestinal tract, as shown by their presence in a form detectable by PCR or immunological tests.’
    Then follows the part referred to:
    ‘However, because the ELISA or immunochromatography kits and immunoblot did not work for blood samples, the present trial
    could not determine whether Cry1Ab was absorbed into the blood.’
    There are a few possibilities.

  11. Feel free to add possibilities:
    1. They were trying to avoid public panic while giving you guys a hint you have not taken.
    2. The kits were modified or updated.

  12. Analysis of 48 blank blood plasma samples by ELISA yielded
    the background values for the Cry1Ab protein ranging from
    0.4 to 1.97 ngmL−1 (mean 0.51 ngmL−1). The decision limit
    (CC) calculated from the mean signal to noise level was
    1.53 ngmL−1. When same 48 blankswere fortified with Cry1Ab
    protein at the concentration level of CC (1.5 ngmL−1), the
    values ranged from 1.21 to 3.51 ngmL−1 (mean 1.57 ngmL−1;
    S.D.S 0.49 ngmL−1). The detection capability (CC) calculated
    from the equation CC=CC + 1.64×S.D.S was 2.30 ngmL−1
    (Fig. 4(a)). The observed Cry1Ab protein values for the blanks
    fortified at concentration level of CC (2.30 ngmL−1) ranged
    from 1.81 to 5.53 ngmL−1 (mean 2.46 ngmL−1). There was no
    overlap between the blanks and fortified samples (Fig. 4(b)).
    Detection capability (2.30 ngmL−1) and threshold value of
    1.81 ngmL−1 (the lowest observed 2.30 ngmL−1 fortified sample)
    laid the basis for selection of the samples for confirmatory
    analysis. Hence, samples with a concentration level at and
    above 1.81 ngmL−1 must be analyzed by any other confirmatory
    method to draw a final conclusion. The assay -error
    is zero since no false negative (false compliant) results were
    obtained for 2.30 ngmL−1 fortified blood plasma samples. This
    satisfies Decision 2002/657/EC [27] which states that screening
    assaysmust “have a false compliant rate of <5% (ˇ-error) at the level of interest”. Similarly, the -error (false non-compliant) is <5% as 2 blank values exceeded the CC (1.53 ngmL−1) value. Both CC and CC values satisfy 2002/657/EC Commission Decision,
    the criteria for the performance and validation of screening
    and quantitative analytical methods.
    http://www.lfl.bayern.de/ite/rind/35021/linkurl_0_2_0_6.pdf
    Theres some symbols which come out different in the cut and paste. Its part 3.3. Possibly the key:
    'Hence, samples with a concentration level at and above 1.81 ngmL−1 must be analyzed by any other confirmatory method to draw a final conclusion.'

  13. I think you need to say more Orphadeus, so that others can understand where you are leading. A hint about what?
    Its not new that Bt is not completely digested in food. The observation appears in at least one other article. The experiments are to address concerns that Bt might get inside the body. These are concerns that are held by many members of the public. That does not make them scientifically plausible, but is a reason for Europeans agencies to check them out, in my opinion.

  14. 3. It is possible that the posts on this website have correctly assessed the Aris and Leblanc paper as misrepresentative and innacurate.
    https://biofortified.org/2011/04/nonsense/#comments
    Comment of Walter Bliss (wbliss), employee at Agdia (developer of ELISA test):
    “Our Bt diagnostic tests were developed and intended for use in plants period. Any other use is simply not valid and certainly not endorsed by our company.”
    Of course, then again, I am part of the corporate conspiracy and I only look for information that confirms my pre-conceived beliefs. Well, at least I am able to identify my own bias…

  15. For greater clarity…I hope everyone understands that the last paragraph about corporate conspiracy a comment about me and not about wbliss and his quote found in the linked page.

  16. This stuff is arcane and irrelevant: The original study NEVER controlled for those who ate “GM corn” versus those who didn’t eat it. They have no idea whether the alleged detection of Bt arose from the protein on corn food, organic food, or dirt on food.

  17. I’ll try to piece together the jigsaw parts. I found the wording interesting:
    ‘The gastrointestinal contents were positive for Cry1Ab protein by ELISA, immunochromatography, and immunoblot; however, these methods did not work for blood and precluded conclusions about any potential absorption of the protein. These results suggest that ingested corn DNA and Cry1Ab protein were not totally degraded in the gastrointestinal tract, as shown by their presence in a form detectable by PCR or immunological tests.’
    http://www.somloquesembrem.org/img_editor/file/detecciopanisBt11tocinosChowdury.pdf
    Thats 2003. Leaving aside that immunological tests appear to be blood tests, the following is from 2008:
    ‘Analysis of 48 blood bank samples by ELISA yeilded the background values for the Cry1Ab protein ranging from 0.4 to 1.97 ngMl-1..
    3.3 at http://www.lfl.bayern.de/ite/rind/35021/linkurl_0_2_0_6.pdf
    The passage continues and appears to confirm ELISA is fine for testing for Cry1Ab in the blood, with the proviso:
    ‘Hence, samples with a concentration level at and
    above 1.81 ngmL−1 must be analyzed by any other confirmatory
    method to draw a final conclusion.’
    Rather than question whether that was known in 2003, lets look at the method used in ‘Maternal And Fetal Exposure To Pesticides Associated To Genetically Modified Foods In Eastern Townships Of Quebec, Canada’:
    http://www.laleva.org/eng/docs/ReproductiveToxicology.pdf
    2.4 states: ‘Cry1Ab protein levels were determined in blood using a commercially available double antibody sandwich (DAS) enzyme-linked immunosorbent assay (Agdia, Elkhart, IN, USA), following manufacturer’s instructions.’
    That appears to refer to ELISA. Do you have evidence that the manufacturer’s instructions were wrong, or that they were not followed?

  18. That appears to refer to ELISA. Do you have evidence that the manufacturer’s instructions were wrong, or that they were not followed?

    Yes.
    Walter Bliss from Agdia states –
    “Our Bt diagnostic tests were developed and intended for use in plants period. Any other use is simply not valid and certainly not endorsed by our company.”
    Or one can go to Agdia’s website where it clearly states what the kits are designed to be used for
    “This assay is suitable for testing both seed and leaf.”
    Which is repeated again in the instructions for the kit.
    If you use the kit on material other than leaf or seed you are not following the manufacturers instructions.

    Thats 2003. Leaving aside that immunological tests appear to be blood tests, the following is from 2008:

    It doesn’t matter that one can use ELISA to detect Cry proteins in blood, you have to use the correct setup (and at a glance the paper you link is precisely about developing a setup that works), the Quebec study used the wrong setup and therefore their results are meaningless, perhaps if they’d used the methodology in the 2008 paper you link (after validating it in human blood spiked with various concentrations of Cry proteins) then they’d have had meaningful results (which would likely never be brought up as they wouldn’t find cry proteins in blood and would have got zero press – based on the findings in the 2008 paper where cows fed diets containing GM and non-GM feed had no detectable Cry levels in their blood)

  19. “Our Bt diagnostic tests were developed and intended for use in plants period. Any other use is simply not valid and certainly not endorsed by our company.”
    wbliss, employee at Agdia as posted in the comments of:
    https://biofortified.org/2011/04/nonsense/#comments
    Please look at the profile of Walter Bliss contained on Biofortified for his background.

  20. Thats all well and good. Unfortunately, at this page –
    https://orders.agdia.com/InventoryD.asp?attribute_Size=&collection=PSP+06200&loc=IN
    – I am unable to check the user guide link due to the computer I am currently using.
    What you are doing with the manufactures quote appears unacceptable, (unless), going by section 3.3:
    http://www.lfl.bayern.de/ite/rind/35021/linkurl_0_2_0_6.pdf
    The two issues:
    1. Was the concentration level at or above 1.81 ngmL−1?
    2. How was corn DNA and Cry1Ab detected by PCR and immunological tests if they were not in the blood?
    In answer to question 1: ‘The authors reported average values of 0.19 nanograms per milliliter (ng / ml) of blood from pregnant women.’
    http://www.gmwatch.org/latest-listing/1-news-items/13450-scientists-rebut-of-critique-of-bt-toxin-in-human-blood-supplyFarmers
    Unfortunately I’m unable to open studies at the moment. However, if the 0.19 is correct, it would appear there was no procedural problem.
    Or do you want to point out that there are different manufacturers and/or versions of ELISA?

  21. “Unfortunately I’m unable to open studies at the moment. However, if the 0.19 is correct, it would appear there was no procedural problem.”
    Yes, there was. The test is not properly calibrated. It’s like testing the pressure in a tire with a gauge that is inaccurate. Do you trust the result? Short answer for the analogy: No.

  22. I can open pages now. There are different ELISA kits:
    ‘Sample Extraction Buffer: The Bt-Cry1Ab/1Ac ELISA must be used with 1X PBST wash buffer for optimal results. Do not
    use sample extraction buffers used with other ELISA kits.’
    https://orders.agdia.com/Documents/m172.pdf
    I cannot see anything that would preclude that particular ELISA kit from testing blood. With seeds and leaves you are instructed to grind and dilute.
    I am going to quote from the article you have attempted to smear. At 2.3.2.:
    ‘The calibration curves and serum samples were extracted by employing a solid phase extraction (SPE) technique, modified from manufacturer’s recommendations and from Motojyuku et al. [16]’
    At 2.4.:
    Cry1Ab protein levels were determined in blood using a commercially available double antibody sandwich (DAS) enzyme-linked immunosorbent assay (Agdia, Elkhart, IN, USA), following manufacturer’s instructions. A standard curve was prepared by successive dilutions (0.1–10 ng/ml) of purified Cry1Ab protein (Fitzgerald Industries International, North Acton, MA, USA) in PBST buffer. The mean absorbance(650 nm) was calculated and used to determine samples concentration. Positive and negative controls were prepared with the kit Cry1Ab positive control solution, diluted 1/2 in serum.
    http://www.laleva.org/eng/docs/ReproductiveToxicology.pdf
    Whats wrong with it?

  23. A simple question:
    The ELISA test in question works by the same principle as an ELISA test that tests blood, is the same as an ELISA test that tests blood, and has been marketed for sale to the general public as a test for seeds and leafs.
    True or false?

  24. What you are doing with the manufactures quote appears unacceptable, (unless), going by section

    I’d assume this is because you haven’t the first bloody clue about the use of, or manufacture of ktis to be used in the biosciences. The 2008 paper describes the specifics of an ELISA test for Cry proteins in blood, they do this, as anyone remotely familiar with ELISA tests (ie not you) knows that to be accurate you need conditions which work with your actual sample and protein, not just something kinda close – how else does one explain why there is a whole paper dedicated to describing the development of an assay for use with blood if any old assay would work. If the manufacturers of a kit flat out say “this kit cannot be used for this purpose” then guess what – you can’t use it for that purpose (they state in the article that they followed the instructions, which is patently untrue as the instructions say to use the kit for seed and leaf tissue)

    Whats wrong with it?

    This question has been answered multiple times (there are numerous things wrong with it). Your stupidity does not make the answers wrong.

    The ELISA test in question works by the same principle as an ELISA test that tests blood, is the same as an ELISA test that tests blood,

    same principle, different conditions, my neighbors lawnmower works by the same principle as my Oldsmobile Alero, I don’t however suggest it would be just as good for driving to work in.

  25. Back to 2008:
    ‘A number of ELISA [21–25] and commercial kits (QuantiPlate kit for Cry1Ab/Cry1Ac, Envirologix and DAS ELISA kit for Bt-Cry1Ab/1Ac protein, Agdia) are already existing for the detection and quantification of Cry1Ab protein expressed in GM crops and their by-products. These commercial kits have been also used in various livestock feeding studies on GMO for the surveillance of transgenic protein in the animal tissues and gastrointestinal contents [17–20,26]. Though the commercially available Cry1Ab protein ELISA kits (QuantiPlate kit for Cry1Ab/Cry1Ac, Envirologix and Agdia) were reported to detect Cry1Ab protein down to 1 ng mL−1 of spiked blood [26], however, the study missed the most important assay validation part. Further, in another study [19] the same ELISA kit (Envirologix) did not work for the analysis of blood plasma for the surveillance of transgenic protein. Hence, such commercial kits designed for transgenic protein (Cry1Ab or Cry1Ac) quantification in plant materials warrants for a proper assay validation before used for protein analysis in animal systems.’
    http://www.lfl.bayern.de/ite/rind/35021/linkurl_0_2_0_6.pdf
    That specifically refers to the kit in question. The proper assay validation is given in that very study.

  26. That specifically refers to the kit in question. The proper assay validation is given in that very study.

    What are you blithering about? They specifically cite the kit in question and specifically point out that without proper validation (which isn’t present in either the 2008 paper or the Aris paper) it cannot be used for determining Cry levels in blood, they then go on to validate their own methods, not the Agdia kit, the Agdia kit does not have any validation for this use in either paper.
    The paper (19) brought up specifically points out that the Envirologix kit (which is likely incredibly similar to the Agdia kit – it too appears to be specific to plants) doesn’t work with blood – which rather puts paid to your ludicrous line of reasoning which appears to be that because one ELISA method works all will.

  27. Ewan, I have just noticed theres at current a very strange phenomena in that the part I quote in my previous post appears at 2 points, both in the introduction and, word for word, immediately before the conclusion:
    http://www.lfl.bayern.de/ite/rind/35021/linkurl_0_2_0_6.pdf
    I hope you checked. Where it appears first backs what I was saying, where it appears 2nd backs you. It appears at current that the paper has been tampered with.

  28. Its this:
    ‘Though the commercially available Cry1Ab protein ELISA kits (QuantiPlate kit for Cry1Ab/Cry1Ac, Envirologix and Agdia) were reported to detect Cry1Ab protein down to 1 ng mL−1 of spiked blood [26], however, the study missed the most important assay validation part. Further, in another study [19] the same ELISA kit (Envirologix) did not work for the analysis of blood plasma for the surveillance of transgenic protein.’
    It appears that either someone has added it to the introduction, or someone has added it to the end (just before the conclusion). Contextual analysis points to someone has added it to the end.
    Matter for the police?

  29. Or that the writers of the document utilized the same piece of text which in neither instance backs your inane ramblings.
    Which is exactly what happened. Clearly.
    Although perhaps the introduction and the conclusion are entagled at a quantum level reducing the harmonic achievements vis-a-vis the universe into a trans-substantiated form predestinated and indeed predetermined to coitally mess with your intercranial transmattertude.

  30. Can I suggest that we leave Orphadeus going round and round trying to find reasons for ignoring the clear statement in Paul et al and from Agdia representative plus the Agdia webpage that the assay used by Aris and Leblanc is not valid for blood samples. That, together with the low near baseline signal reported by A and L confirms the interpretation that A and L measured insignificant assay noise.
    Further conversation will be unproductive until Orphadeus address this issue directly.
    When a scientific paper says something, it generally means what it says.

  31. Rather than keep going round the merry go round:
    Would corn DNA and Cry1Ab have been detected in PCR or immunological tests without having been in the blood?

  32. ‘These results suggest that ingested corn DNA and Cry1Ab protein were not totally degraded in the gastrointestinal tract, as shown by their presence in a form detectable by PCR or immunological tests.’
    http://www.somloquesembrem.org/img_editor/file/detecciopanisBt11tocinosChowdury.pdf
    While you consider that..
    Theres a rudimentary reason why corn DNA and Cry1Ab would be more likely to enter pigs blood than cows. Cows have a ruminent digestive tract whereas pigs (and humans) have a monogastric (simple) digestive tract.

  33. The link you give is one of the studies I was referring to earlier showing incoplete digestion (only 92%).
    “Theres a rudimentary reason why corn DNA and Cry1Ab would be more likely to enter pigs blood than cows. Cows have a ruminent digestive tract whereas pigs (and humans) have a monogastric (simple) digestive tract.”
    That’s an interesting comment, but why not the reverse, and the rumen would allow more complete digestion?.

  34. ” The ELISA test in question works by the same principle as an ELISA test that tests blood,”
    TRUE
    “is the same as an ELISA test that tests blood,”
    FALSE, in that the it is not validated as a test that works “accurately in blood
    ” and has been marketed for sale to the general public as a test for seeds and leafs.”
    TRUE, only for that application

  35. Except if you read elsewhere there are explicit statement that even if you perform the tests as described on blood samples, the results will not necessarily be valid. That’s what’s wrong.

  36. You mean putting the same in the reverse way? ‘Corn DNA and Cry1Ab would be less likely to enter cow blood than pig blood’. Whichever way, its maybe something scientists should point out in their studies. Otherwise, if there are seemingly conradicting studies on cows and pigs, people may be puzzling as to who falsifying data. I had been trying to work that out, hence I checked to see if there would be any difference with digestion. It would appear the difference may be large.

  37. Theres a general concern I have about the compartmentalisation of science. Lets say theres areas a, b and c; in area a is something relevant to area c. Scientists in area c generally do not study area a, and vice versa. Its a general concern. With biology, there are many topics, here’s a list:
    http://en.wikipedia.org/wiki/Biology#Branches_of_biology
    Could it be that some people who have studied say biotechnology have not studied, for example, mammalogy?

  38. In practice, this is exactly what happens. However, it’s not as detrimental as you’d think.
    I work in an entomology lab. The guy who helps me make my experiments work is a biochemist who wouldn’t know a Diaspid from a Stylopid. Despite that, that really isn’t a part of his work. He looks at what happens in caterpillar blood when they get sick, which is ultimately a biochemical process. He also trains young entomologists (such as myself) in the field of biochemistry.
    Want to know what’s happening with the insect on a molecular level? Ask a biochemist.
    We come in handy when it’s time to test the system out in the real world. Want to know what a real insect pathogen is? Want to keep it in your lab? Want to know if the experiment you just did would likely reflect real world conditions? Want to know about potential applications for your experiment (E.G. will this control a pest?) Ask an entomologist.
    Science is cooperative for exactly this reason.

  39. I think like many of us laypeople, we have no idea what “assay validation” means in general terms…so it all ends up sounding like gobbly-gook.
    So yeah, pretending we’re 5th graders, what did that mean?

  40. An assay is basically an experiment to quantify something. Assay validation is making sure that the experiment you’re doing to quantify things works in the conditions you want it to work in.
    So if you are testing for a particular protein in blood using the ELISA method. (doing an ELISA assay for that protein in blood) your first step, rather than looking at blood you think the protein might be in, is to take blood that you’re as certain as can be the protein isn’t in and see if your method works. (and the range over which it works – which you’d do by adding known quantities of your protein of interest to blood you’re sure is devoid of the protein in the first place and then making sure you get a response which is meaningful and can be used to assess unknown quantities of the same protein)
    That’s a bit of a simplification of what assay validation may entail but I think it covers the general gist – basically you’re asking the question “Can my experiment work using this method”

  41. Thanks. I think I’m getting it now. So the problem here in that there is no indication that they, nor anyone else had done this for their method with bt?

  42. I have worked in the lab for 20 years so I know enough about how to get the results you want to get or to ignore the ones that don’t fall in “right” line :-)… regardless of what the analysis showed or did not show the GMOs are not safe and this is the end of the story…
    http://www.i-sis.org.uk/Syngenta_Charged_for_Covering_Up_Livestock_Deaths_from_GM_Corn.php
    http://www.cbsnews.com/8301-201_162-57459357/grass-linked-to-texas-cattle-deaths/
    http://www.dvorak.org/blog/2012/06/27/texas-cattle-die-after-eating-genetically-modified-grass/
    who wants a GMO treat is more than welcome to treat him/herself but please be considered and keep it for yourself

  43. Does this involve much publishing to peer reviewed journals and having people try to replicate your work despite your shenanigans?
    Also…did you just admit to fraud? …little uncomfortable now.

  44. The first site seems to only reference itself or says if you want sources you need to become a member…kind of a weird practice for people that would want to get the information out there.
    The second site deals with speculation on hybrid grass naturally mutating, which if anything would seem to argue that hybrids and natural uncontrolled mutation, (let alone irradiated crops for accelerated mutations), both of which undergo no safety testing whatsoever, can be potentially harmful as well…did I mention that despite this they enjoy no regulation for safety?
    And as Bodnar points out, the last site’s comments further clear up the Tifton 85 story. As one guy puts it “Tifton 85 is a Bermuda grass hybrid, not a GMO. Prussic acid poisoning is a known issue with several kinds of forage plants, especially when the plants are under drought stress. What happened here is extremely rare, but not completely unheard of.”
    Anyway, I’m now starting to see what you mean by “how to get the results you want to get or to ignore the ones that don’t fall in “right” line”. Just go read a bunch of stories that buy into your preconceptions and don’t cross-check any of the claims.

  45. I have not created the commercialized GE crops, but I do eat them. I do not yet have kids, but they will likely eat them as well. There is a perception in some circles that plant scientists at companies or academia somehow must believe it is dangerous, and so they do not eat it themselves. Claims circulate around about the Monsanto cafeterias, for instance, do not serve GE foods. All of this is untrue to the best of my knowledge.

  46. What is the implication there, that scientists are evil and know these things are bad for you but are putting them out there anyway? But the tell tale sign is that they avoid them too?
    Well they aren’t, and they don’t.
    Scientists are people, like you and like me, they have families, friends, loved ones they care about, they often may vote the same as you, they often may laugh at the same jokes as you…
    And yes, time to time they’re been known to eat GMOs and feed them to their kids. (We’ve all probably eaten some time to time.)
    In fact I recall a blog where one supporter, not a scientist but a farmer, did exactly that: http://thefarmerslife.wordpress.com/2012/05/28/a-taste-test-of-biotech-sweet-corn/
    Why? Because like a person letting go of a bowling ball on a pendulum, when you know the science you know it’s safe.
    (what I’m referencing there: http://www.youtube.com/watch?v=i2GdY1OlDpA 🙂
    Now stop worrying so much and start asking yourself, what are the basis for your beliefs, and what do others have the say about them?

  47. Daws,
    Thanks for that link to my post. I can’t claim to be as knowledgeable of all the intricacies of biotech as my online agnerd friend Anastasia, but I have had a fair share of education in human, plant, and animal biology while earning my degree at Purdue. My education and the things I continue to learn from sites like this one help me to understand not just the practical application of biotech on my farm, but how traits come to market and their effects in the real world. I still remember getting to do PCR in my genetics lab. I’m certainly no scientist. Four semesters of chemistry was enough for me!

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