The Planned Introduction of Genetically Engineered Organisms: Ecological Considerations and Recommendations
The Planned Introduction of Genetically Engineered Organisms: Ecological Considerations and Recommendations
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DOI：
10.2307/1937535
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发表时间：
1989-04
期刊：
影响因子：
4.8
通讯作者：
J. Tiedje;Robert K. Colwell;Y. L. Grossman;R. Hodson;R. Lenski;R. N. Mack;P. Regal
中科院分区：
文献类型：
--
作者：
J. Tiedje;Robert K. Colwell;Y. L. Grossman;R. Hodson;R. Lenski;R. N. Mack;P. Regal
本报告考虑了计划将转基因生物引入环境的生态和进化方面。这组作者支持及时开发无害环境的产品，例如改良的农业品种、肥料、虫害防治剂和用于废物处理的微生物，通过在基于科学的监管政策的背景下使用先进的生物技术，鼓励创新而不损害健全的环境管理。经济、社会和伦理问题也必须与严格的生态和进化考虑一起加以权衡，但这些其他问题超出了本报告的范围。对计划引进的生态监督应着眼于提高有效性，同时防范潜在问题。将被改造的生物的多样性，将被改造的功能，以及将接受改变的生物的环境，使得生态风险评估变得复杂。虽然我们现在不能建议完全免除特定生物体或性状的监管，但我们支持并将继续协助开发方法，根据客观、科学的标准，扩大个别病例所需的监管水平，目标是尽量减少不必要的监管负担。在本报告中，我们为监管监督的规模提供了一套初步的具体标准。基因工程生物应该根据其生物学特性（表型）而不是根据用于生产它们的遗传技术来评估和调节。尽管如此，由于许多新的性质组合只能通过分子和细胞技术来实现，这些技术的产品往往比传统技术的产品受到更严格的审查。虽然产生精确的基因改变的能力增加了对基因组未发生意外变化的信心，但精确的遗传特征并不能确保能够预测到生物体将被引入的环境中表型的所有生态重要方面。在评估计划将基因工程生物引入环境的潜在生态后果时，必须考虑许多重要的科学问题。这些包括引入生物的生存和繁殖，与环境中其他生物的相互作用，以及引入生物对生态系统功能的影响。我们鼓励在以前的实验室和（或）温室研究证明合理的情况下，在尽量减少扩散的条件下并在适当的管理监督下进行小规模实地试验。随着生物技术产业的发展，持续的监管监督以及长期的研究和监测对于负责任的风险管理是必要的。尽管可能会出现一些重要的例外，但许多工程生物可能会比亲本生物更不适合。即使一种工程性状只略微降低了生物体的适应性，在引入的生物体由于适应性降低而完全消失之前，可能会有几代人过去。当种群更替速度非常缓慢时，这种持久性是最有可能的。自然选择将作用于基因工程生物，就像它作用于所有其他生物一样。转基因生物释放后的选择将倾向于通过降低与新性状相关的成本来增加适应度，而不是降低适应度。如果适合度确实增加，它们可能会提高人口增长率和生物竞争力，或产生在评估风险时应考虑的其他生态效应。将工程基因从被修饰的生物体转移到其他生物体中可以通过在高等生物体中的杂交，或通过在微生物中的偶联、转导或转化发生。如果发生横向转移，工程基因可能会在自然环境中持续存在，即使基因工程生物体本身不再存在。现有的科学证据表明，自然界中微生物之间的横向转移既不罕见到我们可以忽略它的发生，也不常见到我们可以假设现代生物技术所跨越的障碍与自然界中不断跨越的障碍相当。本地物种，以及从遥远栖息地新引进的物种，都可能成为害虫。为了在新的栖息地类型、地理区域或季节中繁荣发展而设计的生物实际上是一种引进生物，因为它可能会进入新的生物和非生物相互作用中。因此，必须谨慎使用依赖于“本地”和“非本地”区分的监管和风险评估结构。人们经常对基因工程生物取代接收群落中常驻物种的可能性表示担忧，特别是发挥木质素分解固氮等关键功能作用的微生物物种。由于功能冗余在微生物群落中似乎很常见，在许多情况下，对引入转基因生物引起的微生物物种位移几乎没有什么关注。生态效应和生物的地理范围超越了政治界限；因此，我们认为必须促进和实现生物技术风险评估和管制的国际协调。必须特别考虑保护稀有遗传资源，如驯化物种的野生祖先和其他野生物种的受威胁基因库。我们敦促地方、州、国家和国际合作，对引进转基因生物的生态影响进行风险评估和管理。评估生物技术产品的利益和风险需要许多科学学科的专业知识，包括分子生物学、遗传学、细胞生物学、进化生物学、生理学、种群和群落生态学以及生态系统科学。为了使社会充分认识到生物技术的好处，需要跨学科的研究和研究生培训计划来扩大科学界的专业知识。
The ecological and evolutionary aspects of planned introductions of transgenic organisms into the environment are considered in this report. The authors support the timely development of environmentally sound products, such as improved agricultural varieties, fertilizers, pest control agents, and microorganisms for waste treatment, through the use of advanced biotechnology within the context of a scientifically based regulatory policy that encourages innovation without compromising sound environmental management. Economic, social, and ethical concerns also must be weighed along with strictly ecological and evolutionary considerations, but these other issues are beyond the scope of this report. Ecological oversight of planned introductions should be directed at promoting effectiveness while guarding against potential problems. The diversity of organisms that will be modified, functions that will be engineered, and environments that will receive altered organisms makes ecological risk evaluation complex. While we cannot now recommend the complete exemption of specific organisms or traits from regulatory oversight, we support and will continue to assist in the development of methods for scaling the level of oversight needed for individual cases according to objective, scientific criteria, with a goal of minimizing unnecessary regulatory burdens. In this report, we provide a preliminary set of specific criteria for the scaling of regulatory oversight. Genetically engineered organisms should be evaluated and regulated according to their biological properties (phenotypes), rather than according to the genetic techniques used to produce them. Nonetheless, because many novel combinations of properties can be achieved only by molecular and cellular techniques, products of these techniques may often be subjected to greater scrutiny than the products of traditional techniques. Although the capability to produce precise genetic alterations increases confidence that unintended changes in the genome have not occurred, precise genetic characterization does not ensure that all ecologically important aspects of the phenotype can be predicted for the environments into which an organism will be introduced. Many important scientific issues must be considered in evaluating the potential ecological consequences of the planned introduction of genetically engineered organisms into the environment. These include survival and reproduction of the introduced organism, interactions with other organisms in the environment, and effects of the introduced organism on ecosystem function. We encourage the use of small—scale field tests , when justified by previous laboratory and/or greenhouse studies, under conditions that minimize dispersal and under appropriate regulatory oversight. As the biotechnology industry develops, continuing regulatory oversight as well as long—term research and monitoring will be necessary for responsible risk management. Many engineered organisms will probably be less fit than the parent organism, although some important exceptions may arise. Even if an engineered trait reduces an organism's fitness only slightly, may generations may pass before the introduced organisms disappears completely due to decreased fitness. Such persistence is most probable when the turnover rate of populations is very slow. Natural selection will act on genetically engineered organisms, as it does on all others. Selection after the release of the transgenic organism will tend to increase fitness, not decrease it, by reducing the costs associated with the novel traits. If increases in fitness do occur, they will probably increase population growth rate and biological competitiveness, or produce other ecological effects that should be considered in assessing risks. Transfer of engineered genes from the modified organism to other organisms may occur through hybridization in higher organisms, or through conjugation, transduction, or transformation in microorganisms. If lateral transfer occurs, an engineered gene may persist in the natural environment even after the genetically engineered organism itself is no longer present. The available scientific evidence indicates that lateral transfer among microorganisms in nature is neither so rare that we can ignore its occurrence, nor so common that we can assume that barriers crossed by modern biotechnology are comparable to those constantly crossed in nature. Native species, as well as species newly introduced from distant habitats, may become pests. An organism engineered to prosper in a new habitat type, geographic area, or season is effectively an introduced organism in that it will probably enter into new biotic and abiotic interactions. Therefore, regulatory and risk assessment structures that rely on the distinction between ~`native" and ~`non—native" must be used with caution. Concern has frequently been expressed regarding the potential for genetically engineered organisms to displace resident species in the receiving community, particularly microbial species performing key functional roles such as nitrogen fixation of lignin decomposition. Because redundancy of function appears to be common in microbial communities, in many cases there would be little concern over microbial species displacement caused by an introduced transgenic organism. Ecological effects and the geographic ranges of organisms transcend political boundaries; we therefore consider it essential to promote and achieve international coordination of risk assessment and regulation of biotechnology. Special consideration must be given to the protection of rare genetic resources, such as the wild ancestors of domesticated species, and threatened gene pools of other wild species. We urge local, state, national, international cooperation in risk assessment and regulation of the ecological effects of the introduction of transgenic organisms. Evaluating the benefits and risks of biotechnology products requires expertise in many scientific disciplines including molecular biology, genetics, cell biology, evolutionary biology, physiology, population and community ecology, and ecosystem science. For society to realize the full benefits of biotechnology, interdisciplinary research and graduate training programs are needed to expand the expertise of the scientific community at large.