Biotechnology An Industry Comes of Age (1986) / Chapter Skim
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The Release of Genetically Engineered Organisms into the Environment
The Release of Genetically Engineered Organisms into the Environment
Pages 54-63
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From page 54... ...
In addition to offering dramatic new capabilities, the use of genetically engineered organisms in the environment will raise a host of new concerns. Most natural ecosystems are exceedingly complex assemblages of many different organisms and abiotic influences, and many of the relationships among an ecosystem's components are still poorly understood.
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From page 55... ...
Understanding the issue therefore requires a much more detailed examination of the specific factors involved when a new organism is introduced into the environment. The Components of Environmental Risk According to Martin Alexander of Cornell University, five independent factors come into play in determining what effect a genetically engineered organism will have on other organisms.
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From page 56... ...
In addition, DNA may be transferred between organisms in the environment, either sexually or asexually, and this must also be taken into account in calculating the risk posed by a genetically engineered organism. Release Obviously, an organism must first enter the environment to cause harm.
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From page 57... ...
A few bioengineered organisms designed for use in the environment, including microbial pesticides and genetically engineered crops, have already been produced and studied within laboratories, growth chambers, and greenhouses. Experiments involving these organisms carried out with public funds are required to adhere to the appropriate containment procedures specified in NIH's Guidelines for Research Involving RecombinantDNA Molecules (the history of these guidelines appears in Chapter 6)
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From page 58... ...
In plant ecology, animal ecology, and microbial ecology, it is known that an introduced organism does occasionally survive." Alexander's own research and the studies of other microbial ecologists have revealed many instances of microorganisms from foreign locations that survive for days, weeks, months, and even years when introduced into new environments. The past history of introduced plants, animals, and microorganisms that have done great environmental damage, while admittedly worst-case examples, also indicates that some percentage of introduced organisms will survive.
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From page 59... ...
"If the acquisition of one characteristic results in an ecological advantage, then the organism may be able to overcome one of the environmental barriers to its establishment. Unfortunately, at this time, we can't tell whether additional DNA that is disadvantageous in one way will also be advantageous in another way." Furthermore, one could argue that it is unlikely that a genetically engineered organism would acquire a newfound persistence, as in the case of a weed or rampant pathogen, because many interacting genes are needed to generate such characteristics.
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From page 60... ...
To take just one example from traditional plant breeding, a specific cultivar of potato had to be removed from supermarket shelves because it was found capable of producing hazardous levels of toxins under certain conditions of stress. Such unintended effects may be less likely to occur with recombinant DNA techniques than with traditional plant and animal breeding, since the genes and metabolic pathways to be altered are likely to be more fully characterized with recombinant DNA.
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From page 61... ...
Furthermore, the uncertainties will loom larger as more and more organisms are altered, as the number and kind of introduced genes grow, and as genetically engineered organisms are released into
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From page 62... ...
Researchers should concentrate on several key points, according to Alexander. Most important, the specific factors that contribute to the probabilities associated with each of the six components of environmental risk should be identified.
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From page 63... ...
"If one has a good base of scientific information and a reasonable testing system, then I think that much of the residual degree of uncertainty can easily be answered by a very modest regulatory program," says Alexander. "But we should have a regulatory system in place, a regulatory system that will reduce the likelihood of a problem arising, and a significant amount of research to find out where the issues are." Additional Readings Martin Alexander.
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