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.