Assessment of Allergenicity in Genetically Modified Herbicide-Resistant Foods Using the Serum Screening Test / 소아알레르기및호흡기학회지

PURPOSE: This study aimed to evaluate the potential allergenicity of genetically modified (GM) herbicide-resistant food by using the serum screenning test. METHODS: Children with allergic disease were recruited, and those who were sensitized to soybean, corn or peanut were selected to obtain their sera. Sensitization to these food allergens was determined when the level of specific IgE was over 0.35 kU/L using ImmunoCAP (Pharmacia, Uppsala, Sweden). Immunoblot analyses were performed for soybean (n=50), corn (n=50) and peanut (n=20). Newly inserted gene was sequenced and cloned from GM soy (Roundup Ready Soybean, Monsanto), GM corn (Bt 11, Syngenta) and GM canola (MS8/RF3 canola, Bayer CropScience). These proteins, such as CP4 EPSPS, PAT, and BAR, were expressed and purified for the serum screening test. RESULTS: Immunoblot analysis using CP4 EPSPS and sera from soybean-sensitized children showed no bands. Likewise, sera from corn-sensitized children and PAT did not demonstrate IgE binding in immunoblot analysis. In addition, there were no reactions between BAR and sera from peanut-sensitized patients. CONCLUSION: The serum screening test using sera from allergic children and newly inserted protein (CP4 EPSPS, PAT and BAR) in GM soybean, GM corn and GM canola failed to show IgE binding in immunoblot analysis. The results of this study suggest that these newly inserted proteins may not cause allergic disease. Further studies using more sera from allergic children are needed to conclude the safety of herbicide-resistant GM food.

Allergenicity of Genetically Modified Crops / 소아알레르기및호흡기학회지

During the period 1996 to 2006, 51 countries have granted regulatory approvals for genetically modified (GM) crops for import for food and feed use and for release into the environment. A total of 539 approvals has been granted for 107 events for 21 crops. One of the safety concerns regarding GM crops is potential allergenicity of the inserted protein. In safety-assessment of the allergenic potential from GM crops, the allergenic properties of the gene donor and the host organisms should be evaluated. The sequence of the newly introduced protein should be compared with all known allergens. If a sequence homology match to a known allergen is identified for the introduced protein, then this protein should be assessed for immunoreactivity using sera from allergic patients. If no sequence homology to known allergens is identified, then the stability of the protein to digestion and processing is assessed. Currently, laboratory and clinical tests have been reported and the assessment process of GM crops has worked well to prevent the unintended introduction of allergens. However, these tests may still occasionally miss a new allergen from all novel foods containing GM crops. The newly introduced protein in GM crops must be carefully assessed as proteins may induce allergic reactions in humans.

Molecular analysis of hprt mutation in B6C3F1 mice exposed to ozone alone and combined treatment of 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone and/or dibutyl phthalate for 32 and 52 weeks

Potential toxicological interactions of 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and/or dibuthyl phthalate (DBP) on ozone were investigated after 32- and 52-wk exposures using hprt mutation assay. Male and female B6C3F1 mice exposed to ozone (0.5 ppm), NNK (1.0 mg/kg), DBP (5,000 ppm), and two or three combinations of these toxicants 6 h per day for 32- and 52-wk showed increases in the frequencies of TG rlymphocytes compared to the control groups. Additive interactions were noted from two combination groups compared to the ozone alone in both sexes of 32- and 52-wk studies. The most common specific mutation type in the hprt genes of test materials-treated male and female mice was transversion with very few transition. The results indicate that such dominant transversion may be responsible for toxicity and combined exposure to ozone, NNK, and DBP induces additive genotoxicities compared to ozone alone.