reerpe om the articte emetically Modified Organism s IMO Tranagenie Crops and Recom binant DNA Technotogu There Phillie, P D ite Scienee Right)e 2oos Nature Education Unintended hpaote on Other Species: The Bt Corn Controversy case of Bt corn. Bt corn expresses a protein from the bacterium Bacillus thuringiensis. Prior to construction of the recombinant corn, the protein had long been known to be toxic to a mumber of pestiferous insects, including the monarch caterpillar, and it had been successfully used as an environmentally friendly insecticide for several years. The benefit of the expression of this protein by corn plants is a reduction in the amount of insecticide that farmers must apply to their crops. Unfortunately, seeds containing genes for recombinant proteins can cause unintentional spread of recombinant genes or exposure of non-target organisms to new toxic compounds in the environment. One example of public debate over the use of a genetically modified plant involves the The now-famous Bt corn controversy started with a laboratory study by Losey et al. (1999) in which the mortality of monarch larvae was reportedly higher when fed with milkweed (their natural food supply) covered in pollen from transgenic corn than when fed milkweed covered with pollen from regular corn. The report by Losey et al. was followed by another publication (Jesse & Obrycki, 2000) suggesting that natural levels of Bt corn pollen in the field were harmful to monarchs. Debate ensued when scientists from other laboratories disputed the study, citing the extremely high concentration of pollen used in the laboratory study as unrealistic, and concluding that migratory patterns of monarchs do not place them in the vicinity of corn during the time it sheds pollen. For the next two years, six teams of researchers from govermment, academia, and industry investigated the issue and concluded that the risk of Bt corn to monarchs was "very low" (Sears et al., 2001), providing the basis for the U.S. Environmental Protection Agency to approve Bt corn for an additional seven years. Guide Questions: Q1. What are the benefits and risks of using GMOS specifically the BT corn as mentioned in the selection? Q2. Knowing the benefits and risks of the use of BT corn in the selection, what do you thínk are the impacts of this GMO in the Philippine industry? Q3. If you were a farmer, would you choose to plant BT corn in your farmland after knowing the benefits and possible threats of the GMO to biodiversity? Why or Why not?