Ecologists such as Jane Rissler and Margaret Mellon who have opposed the release of transgenic organisms since the 1980s, have predicted those ecological effects . A potentially greater danger A potentially even greater danger lies in the vector-mediated gene transfer, as recent evidence suggests. These microbial populations form large reservoirs supporting the multiplication of the vectors, enabling them to spread to all other species. There will also be ample opportunity for the genetic elements to recombine with other viruses and bacteria to generate new genetic elements and pathogenic strains of bacteria and viruses, which will, at the same time, be antibiotic resistant. Another major class of transgenic plants is now engineered for resistance to viral diseases by incorporating the gene for the virus' coat protein.
Viruses are notoriously rapid in their mutation rate.
They play a large role in horizontal gene transfer between bacteria and also exchange genes among themselves thus increasing their host range. Molecular geneticists have expressed concerns that transgenic crops engineered to be resistant to viral diseases might generate new diseases by recombination. The infectious virus was indeed regenerated by recombination. As plant cells are frequently infected with several viruses, recombination events will occur and new and more virulent strains can be generated. In the light of our new knowledge, one must also ask whether transgenic foods are safe to eat.