Contents - Faperta

474 Biotechnological Approaches for Pest Management and Ecological Sustainability
(Viljoen, Dajee, and Botha, 2006). Detection of genetically modifi ed food varies across
different foods and food processing (Cazolla and Petrucelli, 2006). Based on PCR screening
for CaMV35S and transgene specifi c primers (CRY and EPSPS), the quantifi cation
within the European Union limits was possible only in case of ice-cream, fl ours, soybean,
and starch. Samples with high lipid content or subjected to intense thermal treatments,
such as snacks, mayonnaise, and creamy soup, etc., could not be amplifi ed mainly due to
the presence of PCR inhibitors.
There are practical diffi culties in labeling the food and food products derived from
genetically modifi ed plants when they are produced and consumed at the village level
without processing and packaging, particularly in the developing countries. Because of
the diffi culties involved in monitoring and detection of genetically modifi ed food and
unregulated mixing, marketing, and consumption of food in the developing countries, it
may not be practical to follow a harmonized system of leveling genetically modifi ed food
the world over. Therefore, it may be more pertinent to ensure the safety and quality of the
genetically modifi ed food during product development and de-regulation stages.
Conclusions
The need for identifi cation and detection of transgenic crops and the food products derived
from them has increased with the rapid expansion in the cultivation of transgenic crops
over the past decade. Labeling and traceability of transgenic material is important to address
the concerns of the consumer. Establishment of reliable and economical methods for detection,
identifi cation, and quantifi cation of genetically modifi ed food continues to be a challenge
at the international level. It is important to know the limitations of each procedure as
well as the purpose of detection. Both the sample size and sampling procedures dramatically
impact the conclusions that may be drawn from any of the testing methods. Currently,
available methods for detecting transgenic crops and their products are almost exclusively
based on PCR, because of sensitivity, specifi city, and the need for only a small amount of
DNA. Real-time PCR has been regarded as a powerful tool for detection and quantifi cation
of transgenic material despite its high cost. There is a need to refi ne other methods for
detection of genetically modifi ed food that are economic, reliable, and sensitive to meet the
future needs for monitoring food and food products for the presence of transgene or transgene
products. In view of the diffi culties involved in detection and monitoring of genetically
modifi ed food, it will be useful to ensure the safety and quality of food derived from
genetically modifi ed plants during the development and testing phases.
References
Berdal, K.G. and Holst-Jensen, A. (2001). RoundupReady ® soybean event specifi c real-time quantitative
PCR assay and estimation of the practical detection and quantifi cation limits in GMO analyses.
European Food Research and Technology 213: 432–438.
Busch, U., Muhlbauer, B., Schulze, M. and Zagon, J. (1999). Screening und spezifi sche Nachweismethode
fur transgene Tomaten (Zeneca) mit der Polymeraskettenreaktion. Deutsche Lebensmittelrundschau,
Heft 2: 52–56.