Source: Moderator, searcabiotech

During the First Meeting of the Parties serving as the Conference of the Parties to the Cartagena Protocol on Biosafety held last week in Kuala Lumpur, Malaysia, Norwegian Scientist Terje Traavik spoke of a report saying that some 39 farmers in Mindanao, Philippines developed immunity to antibodies because of exposure to Bt corn. 

This statement elicited strong responses from the government and scientific community.  We would like to share with you one such response to Traavik's statement from a Professor of Medical Biology and Microbial Immunology of the College of Public Health, University of the Philippines Manila:

RESPONSE TO CLAIMS OF GM CORN POSING “SERIOUS HEALTH THREATS “ TO FILIPINOS LIVING NEAR CORN FIELDS IN MINDANAO, PHILIPPINES
February 27, 2004
by Nina Gloriani Barzaga, M.D.,Ph.D.
Professor of Medical Microbiology & Microbial Immunology, College of Public Health , University of the Philippines Manila
Director of the Institute of Biotechnology and Molecular Biology, National Institutes of Health Philippines
Director for Research , Biotechnology Coalition of the Philippines

The statement made by Norwegian scientist Terje Traavik  that  “blood samples from 39 people in Southern Philippines carried increased levels of three different target antibodies showing evidence of an immune reaction to the Bt toxin built into the maize gene to combat pests”  needs to be evaluated based on the basic principles of  immunology and immunobiology.   Traavik  needs to show pertinent scientific data that establish his claims, before making press releases and unduly causing panic to the public. 

It is  important that Traavik specify which isotypes of antibodies were found to be increased in these individuals, the levels of  increases in these individuals, the specific antigenic epitopes that these antibodies recognized, and his data should also be able to establish that  the presence of these antibodies correlated with clinical signs and symptoms of hypersensitivity (or any biologic activity) among these individuals.  It is also important for  Traavik to indicate what types of tests were performed, and in which laboratories  these tests were performed.   There are accepted standardized and validated procedures used in any allergenicity testing. 

The MON 810 corn which is sold as Dekalb 818 YG in the Philippines has the Bacillus thuringensis toxin Cry 1Ab  which Traavik  referred to as the protein that the Filipinos generated an immune reaction to.  This is a serious allegation and if Traavik is indeed the scientist that he professes to be, he should be able to explain convincingly, how Bt maize pollen which is known to carry the protein at a very low or undetectable level, could have sensitized these Filipinos against the Bt Cry 1Ab protein. 

The Bt cry 1Ab protein that is in the MON 810  corn  has been assessed for allergenic potential based on established criteria and procedures.  This toxin is not considered an allergen. This protein has no sequence similarity to known allergenic proteins based on 8-12 amino acid mapping for T cell and B cell epitopes.  The toxin is also degraded rapidly when subjected to gastric digestibility studies, being degraded in less than 30 seconds, compared to major allergens being stable to gastric digestion for more than 1 hour,  or minor allergens being stable for at least 2 minutes  in simulated gastric fluid. 

Traavik should provide us with the scientific data to prove his claims. 

PHILIPPINES DEPARTMENT OF AGRICULTURE BELIES CHARGES THAT BT CORN CAUSED ANTIBIOTIC IMMUNITY
February 25, 2004 Manila Bulletin
By Melody Aguiba

The Department of Agriculture (DA) has discarded as the “height of absurdity” accusations by a Norwegian scientist that 39 Filipino-farmers have developed an immunity to antibodies in the development of genetically modified Bacillus thuringiensis (Bt) corn because of their exposure to Bt corn.

Artemio M. Salazar, DA corn program director, said that it is impossible for human to develop immunity from certain antibodies by simple exposure to GM corn plants, either by planting it or by eating it.

“It’s ridiculous. It’s the height of absurdity. You should not touch it with a 10-foot pole. It’s absurd. No Biology student will believe it,” he said.

Salazar said that the human gene cannot simply mix with another gene, specially a plant’s gene, just by inhaling it or being physically exposed to it.

“If there’s a chain of molecule of up to 100, if that goes through the human systems, when it’s digested, it will be crushed beyond recognition. It’s impossible it will be left intact. (Besides), it’s an organic molecule. It is impossible that a plant gene will mix with human,” he said.

“If it is impossible for a human gene to mix with another gene without copulation, without mating, how much more will a plant gene change human form under a natural setting,” he said.

Norwegian scientist Terje Traavik said in an international trade conference that 39 farm workers in a GM corn farm in Mindanao have developed the immunity to antibodies due to their exposure to GM corn. Their blood samples, according to Traavik, contained increased levels of three different target antibodies.

Salazar said that genetic modification goes through a difficult process such that a desired gene (resistance to corn borer in the case of Bt corn) is normally injected in a plant together with a marker, particularly antibiotics.

The marker, he said, may have the characteristic of herbicide resistance or antibiotics resistance. Whatever the marker is, the objective of injecting it with the target gene, he said, is for the experimenter to detect whether the target gene has been implanted in a plant or not.

“The marker is what you monitor to verify if the gene of interest is there,” he said.

If the gene is not implanted on the plant, the plant will be killed by the antibiotic.

“But if the Bt gene is there, the plant will live. What scientists do after rewards is to tissue culture the cell until it becomes a full-grown plant. If you put an antibiotic in a plant, the plant will die, if the gene is not there. But if you put this plant (with the gene and antibiotic) in human, it is impossible (that the person will develop immunity) because if you ingest the pollen, when it passes through your gag, it will be crushed into very small pieces. How much more could mere exposure impact on you,” he said.

HEALTH OF MINDANAO FARMERS ADVERSELY AFFECTED BY BT CORN - NORWEGIAN SCIENTIST
February 28, 2004 Philippine Star
By Rocel C. Felix

Agriculture Secretary Luis Lorenzo Jr. has instructed experts of the Department of Agriculture (DA) to verify reports that 39 farmers in Mindanao developed immunity to anti-bodies as a result of exposure to the Bacillus thuriengensis (Bt) corn.

"We want to know if the reports are true so that we could take appropriate measures," Lorenzo said.

Lorenzo said the farmers are being tracked down by the field proposal of the DA in Mindanao, particularly in South Cotabato where Bt corn is being planted.

The report was released by Norwegian scientist Terje Traavik who spoke earlier this week at the international talks on trade in genetically-modified crops in Kuala Lumpur, Malaysia.

Traavik said some farmers in Mindanao, "living by a field planted with genetically modified maize showed signs of exposure to the plant’s anti-pest toxin three months after the pollen season."

He said blood samples taken from these farmers later showed increased levels of three different target antibodies. It identified the corn variety as the Bt corn. Lorenzo said he has not yet seen a copy of the report but he has asked the department’s science and technical experts to conduct an investigation."

Lorenzo also called on Traavik to collaborate with the DA and identify specific areas where the problem allegedly surfaced.

"I would like to encourage these persons or groups who are aware of this incident to coordinate with the government so that we can make the necessary and appropriate action at the soonest time possible."

Traavik will be in Manila next week to explain the report he presented at the talks in Kuala Lumpur.

Moderator, searcabiotech