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Executive Summary
Since genetically engineered organisms (GEOs) were introduced into
the environment nearly 20 years ago, questions have been raised about the
consequences of the escape of those organisms and their engineered genetic
materialtransgenesinto natural and managed ecosystems. Ecological
research has shown that some GEOs are viable in natural ecosystems and
can cross with wild relatives. There also are instances in which transgenes
from one domesticated variety can move to others. As a result, there is
interest in developing methods to confine certain GEOs and their transgenes
to specifically designated release settings. Many confinement methods,
including induced sterilization and other methods, are biological in nature,
whereas others rely on physical restrictions such as greenhouses or aqua-
culture pens. This report refers to these biological methods as bioconfine-
ment. Although bioconfinement of GEOs is still largely in the conceptual
and experimental stages of development, some methods already have been
applied to nonengineered organisms.
The primary mechanism in the United States for regulating GEOs and
the products derived from them is the 1986 "Coordinated Framework for
the Regulation of Biotechnology Products." This framework apportioned
jurisdiction over transgenic products by using existing legislation and al-
lowed the U.S. Environmental Protection Agency, the U.S. Department of
Agriculture, and the U.S. Food and Drug Administration to work together
in assessing the safety of the process and products of genetic engineering. In
May 2000, the federal government conducted a six-month interagency re-
view of its oversight of biotechnology products. The review explored the
boundaries of the framework by focusing on several products that were not
1
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2 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS
developed until the 1990s, and that therefore were not included in the 1986
framework. The review acknowledged that ensuring confinement could
become one of the regulatory requirements for approval and commercial-
ization of some GEOs. In 2001, the U.S. Department of Agriculture re-
quested that the National Research Council's Board on Agriculture and
Natural Resources (BANR) and Board on Life Sciences (BLS) review and
evaluate bioconfinement of GEOs. BANR and BLS organized the Commit-
tee on Biological Confinement of Genetically Engineered Organisms.
The committee's charge was to review and evaluate bioconfinement
methods and report on their application in confining transgenic crop plants,
grasses, trees, fish, shellfish, and other organisms. The committee's report
was to focus on genetic mechanisms, such as induced sterility, but it also
was to identify and discuss other available or possible bioconfinement
methods. The committee was asked to examine the following questions:
· What is the status of scientific understanding about various bio-
confinement methods for genetically engineered organisms?
· What methods are available, and how feasible, effective, and costly
are these methods?
· What do we know about when and why methods fail, and what can
be done to mitigate those failures?
· When these methods are used in large-scale applications, what pro-
cedures can be used to detect and cull individuals for which the bio-
confinement methods have failed? What is the cost effectiveness of these
mitigation, detection and culling procedures?
· What are the probable ecological consequences of large-scale use of
bioconfinement methods (e.g., deployment of sterile organisms) on wild
populations, biological communities, and landscapes?
· What new data and knowledge are required for addressing any of
these important questions?
Although not a focus of the report, the social acceptability of biocon-
finement methods is discussed in the introduction and as context for the
technical analyses.
This report examines bioconfinement of genetically engineered plants,
animals, microbes, and fungi. Particular attention is given to transgenic fish
and shellfish, trees and grasses, and microbes, because many of those species
have been successfully engineered and currently are under federal regula-
tory evaluation. Because the committee was not asked to evaluate govern-
mental practices or policy, it has limited its discussion to the scientific and
societal components that are brought to bear on the process of choosing
and applying bioconfinement of GEOs.
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EXECUTIVE SUMMARY 3
This report consists of six chapters. Chapter 1 defines terms and intro-
duces concepts used throughout the report and briefly overviews the history
and social acceptability of GEO confinement. Chapter 2 addresses the
questions of when and why bioconfinement should be considered and it
provides context for the need for and the application of bioconfinement
methods. Chapters 3, 4, and 5 review and analyze bioconfinement methods
for plants, animals, and microbes, respectively. Chapter 6 reviews the bio-
logical and operational opportunities and constraints for bioconfinement
and examines bioconfinement failures and their mitigation. Chapter 6 con-
cludes with a look to the future, exploring unanswered research questions
that will establish better methods for the bioconfinement of GEOs.
RATIONALE FOR BIOCONFINEMENT
In many cases GEOs will not require bioconfinement, but in some cases
they will. The need for bioconfinement should be evaluated on a case-by-
case basis. The predominant factors for consideration involve the risks
associated with the dispersal of a transgene or transgenic organism into a
place, a population, or a biological community for which it was not intended.
Significant research efforts on new categories of transgenic plants, insects,
microbes, and animals are under way and many of those organisms are
being considered for use or release into the environment. Species that dis-
perse easily can pose particular risks because of the inefficacy of physical
confinement methods and because of the potential for escapees to interact
with and harm wild populations.
Currently, the most publicized environmental risk associated with
transgene dispersal involves the evolution of increased weediness or
invasiveness as a result of the sexual transfer of plant crop alleles to wild
relatives. When domesticates and wild relatives live in proximity, it is not
unusual for natural hybridization to occur. Spontaneous hybridization
between nontransgenic crops and their wild relatives already has led to the
evolution of several weeds and invasive species such as weed beets in Europe
and weed rye in California. It is possible that some engineered genes that
confer pest resistance or otherwise improve a crop plant might contribute
to the evolution of increased weediness in wild relativesespecially if the
genes escape to an organism that already is considered a weed.
A transgenic organism itself can become an environmental problem if
the transgenic traits it expresses alters its ecological performance such that
it becomes an invasive or nuisance species. Many crop plants pose little
hazard because the traits that make them useful to humans also reduce their
ability to establish feral populations in agricultural or nonagricultural habi-
tats. However, feral and naturalized populations are well known for some
crops and domesticated animals. If transgenes confer the ability to over-
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4 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS
come factors that limit wild populations, the resultant genotype might be
significantly more weedy or invasive than is its nontransgenic progenitor.
Other concerns about transgenic organisms include their effects on non-
target populationsincluding humansand the potential for transgenes to
disperse and spread before becoming deregulated in particular regions or
nations. Gene flow from GEOs can greatly increase the extent to which nontar-
get species are exposed to novel proteins. In food crops, transgenes that
code for "novel" pharmaceutical or industrial compounds could be candi-
dates for bioconfinement if dispersal from their site of production is possible.
METHODS OF BIOCONFINEMENT
Many bioconfinement methods have been proposed for limiting the
effects of transgenes. Although those approaches necessarily are tailored to
specific organisms, and the terminology used to describe them is varied, all
bioconfinement methods can be conceptually divided into three general
categories: those that reduce the spread or persistence of GEOs; those that
reduce unintended gene flow from GEOs into other organisms; and those
that limit expression of transgenes.
Plants
Several existing methods target sexual and vegetative reproduction in
plants. For example, sexual reproduction of genetically engineered plants
can be blocked by including a gene that renders the organism either perma-
nently sterile (nonreversible transgenic sterility) or sterile until the applica-
tion of an appropriate trigger is available, such as the use of a chemical
spray on a plant (reversible transgenic sterility). Other methods target pol-
len to confine pollen-mediated gene flow. Those include methods that
achieve male sterility (the inability of a plant to produce fertile pollen) and
those that transform chloroplast DNAwhich usually is inherited mater-
nallyrather than nuclear DNA. An alternative approach reduces the ef-
fects caused by unwanted transgenes by activating a transgenic trait through
a specific artificial stimulus, such as a chemical spray (trait-genetic use
restriction technology). A few of these and other methods are based on
existing agronomic or horticultural practices and have been tested already;
many others are newly developed or are only working hypotheses. Although
the efficacy of some of the approaches is known, most are untested.
Animals
Confinement approaches in aquatic species can be achieved through
physical confinement, through methods that prevent or disrupt sexual
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EXECUTIVE SUMMARY 5
reproduction, or through methods that prevent GEO survival in the wild.
The induction of triploidy is more established as a technique for finfish and
mollusks than for crustaceans. Triploidy is a method that creates, in an
organism, the state of having three sets of chromosomes in each cell nucleus,
rather than the two typically found in most animal cells, which prevents
successful cell division and reproduction. Triploidization is fairly successful
and inexpensive, but like all bioconfinement techniques, it cannot guarantee
100% sterility. If only one sex of the GEO is used in the production opera-
tion--usually the femalethen the likelihood that a self-sustaining feral
population will become established is further reduced. All-female lines often
are used for certain commercial species, and their use in conjunction with
sterility techniques offers great promise. The use of single-sex lines is not a
confinement system on its own, however, if related species that could mate
with the GEOs are found nearby. If GEOs are crossed with related species,
possibly sterile, interspecific hybrids would result, although thorough test-
ing is required to ensure that sterility is close to 100%. Finally, several
approaches could reduce the survivorship of GEOs by making them depen-
dent on humans, either by genetically engineering the organism so that it
requires an anthropogenic substance for its survival or by genetically engi-
neering the organism so that it cannot live without an anthropogenic com-
pound that blocks expression of the harmful gene.
There has not been much research on the bioconfinement of insect
species, and so the subject is not well understood. Sterility is relatively easy
to produce in insects by radiation, and the techniques used to produce and
then quantify sterility are well characterized. However, sterility induced by
radiation also can reduce the fitness of individuals. Any significant reduction
of fitness would likely render the bioconfinement strategy ineffective within
the target population, so transgenic approaches could be used to ensure
sterility in insects without the loss of fitness. The large number of insects in
any population, however, could make even a small failure rate of sterility
techniques problematic.
Microbes
The two major bioconfinement methods used in microbes are pheno-
typic handicapping and the induction of suicide genes. The energetic cost of
expressing the genetically engineered trait after phenotypic handicapping
causes a loss in those organisms' ability to compete well with indigenous
bacteria in soil and aquatic environments. Microbes multiply rapidly and
can mutate, however, so subsequent generations of these bacteria might be
better adapted to the environment than the original GE strain and be able
to coexist with the indigenous populations. The ability to coexist depends
in part on the highly variable external environment. Handicapped fungi
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6 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS
appear to act similarly to handicapped bacteria in that they cannot compete
with indigenous populations. The effectiveness of this mechanism as a con-
finement measure is unclear.
Another major confinement method for bacteria and fungi is the use of
suicide genes. In the case of bacteria, numerous systems have been devised
to significantly reduce the population of bacteria upon the addition or
removal of a chemical or with a change in the environment. In the case of
fungi, several mechanisms have been devised but none have been tested
even in the laboratory. In no case has any method been field tested. Suicide
gene systems have not been used for viruses. Collectively, the methods
remain completely theoretical or have been used in the laboratory, in small
test plots, or in laboratory microcosms.
ENSURING BIOCONFINEMENT EFFICACY
Typically, precommercial evaluation of GEOs starts on a small scale
and then is expanded to larger scales before release. It is likely that appro-
priate bioconfinement methods will be evaluated in a similar way. Never-
theless, these methods will vary in efficacy, depending on circumstances.
Each is likely to work well with a specific organism, genotype, or environ-
ment, to work poorly with others, and to be inappropriate in yet others.
Each is expected to work best on a small spatial scale, and the probability
of failure increases with the number of individuals involved and the size of
the area they occupy. Likewise, each is expected to work best over short
periods of time, and the probability of failure increases with the amount of
the time that the organisms are in the open environment. It is likely that no
single method can achieve complete confinement on its own.
The efficacy of a bioconfinement method will vary depending on the
organism, the environment, and the temporal and spatial scales over which
it is introduced.
Most of the bioconfinement methods for GEOs discussed in this report
are in the early stages of development and much is yet to be understood. It
is clear that there is a great need for additional information on how well
bioconfinement methods work separately and together. The effectiveness of
any method will vary with genotype and the environment. Thus, the effi-
cacy of combining confinement methods should be tested in representative
genotypes that are under development and in environments into which a
GEO is likely to enter to ensure that the plan is effective.
Before field release, the reproductive biology of the novel genotype
should be measured relative to its progenitor to evaluate changes that might
affect its rate of gamete and progeny production and dispersal. New geno-
types generally do not have reproductive phenotypes that are different from
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EXECUTIVE SUMMARY 7
those of their parents, but any changes that do occur could have important
consequences. Changes in the reproductive biology of a GEO might not be
anticipated because of its transgenes, but unanticipated phenotypic effects
of a single allele are not rare.
· To evaluate changes in reproductive biology, the novel genotype
should be compared with its progenitor before field release. For long-lived
species, such as trees, it may be necessary to begin field tests before such
comparisons are possible, with a realistic plan to mitigate any unexpected
and dramatic increase in reproduction.
· Confinement techniques should be experimentally tested, separately
and in combination, in a variety of appropriate environments and in repre-
sentative genotypes under development before their application. In the case
of long-lived organisms such as trees, they should be tested in conjunction
with the release or scale-up of GEO products that are considered safe.
The evaluation of whether and how to confine cannot be an after-
thought in the development of a transgenic organism. Safety must be a
primary goal from the start of any project. Furthermore, it is important to
consider the dispersal biology and the opportunities for the unintentional
movement of transgenes in determining the best choice of an organism for
use in creating a GEO. The constant and iterative evaluation of confine-
ment options during the development of a GEO should optimize both the
efficacy and the cost-effectiveness of the confinement options once they are
deployed. Hurried consideration of confinement just before the deployment
of a GEO will create a makeshift and expensive plan that might work better
in theory than in practice.
The need for bioconfinement should be considered early in the develop-
ment of a GEO or its products.
Many opportunities to mitigate the effects of a bioconfinement failure
can be put in place during the earliest stages of development. For example,
the act of choosing which GEOs to develop is in fact one form of bio-
confinement. An organism that is typically grown to produce a common
and widespread food product probably would be a poor choice as a pre-
cursor for an industrial compound unless that organism were to be grown
under stringent conditions of confinement. This is an important issue for
any novel compound or GEO for which zero tolerance of bioconfinement
failure is needed. Engineering organisms that are not otherwise used for
food or feed could be an effective way to prevent a transgenic compound
from entering the human food chain.
Alternative nonfood host organisms should be sought for genes that
code for transgenic products that need to be kept out of the food supply.
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8 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS
Given that no single bioconfinement technique is likely to be com-
pletely effective, the use of multiple techniques with different strengths and
weaknesses will decrease the probability of failure. Many bioconfinement
techniques are in the early stages of development, and some will be
unacceptable in various circumstances. Therefore, before a GEO is released,
its bioconfinement techniques should be tested in appropriate environments
and in representative genotypes under development, and the reproductive
biology of the GEO should be elucidated relative to its progenitor.
If a bioconfinement method is applied, the committee proposes that a
new approachan integrated confinement system (ICS)should be used.
ICS is a systematic approach to the design, development, execution, and
monitoring of the confinement of a specific GEO. Among its features are a
commitment to confinement by top management; the establishment of a
written plan for confinement measuresand their documentation and
remediation (in case of failed confinement); training of employees; assign-
ment of permanent employees to maintain the continuity of the system;
development and implementation of standard operating procedures; use of
good management practices; periodic audits by an independent entity to
ensure that practices are in place; periodic review adjustment to permit
adaptive management of the system; and reporting to an appropriate regu-
latory body. For ICS to be effective, it is essential that it is supported by a
rigorous and comprehensive regulatory regime that is empowered with
inspection and enforcement.
An integrated confinement system that is based on risk assessment
(including the risk of human error) is recommended.
There also is a need to defineearly onwhat constitutes adequate
bioconfinement. This requires an evaluation of failures, their effects, and
their probabilities under worst-case scenarios. It also entails the assumption
that escaped genes have the opportunity to multiply.
The stringency of the integrated confinement system, including bio-
confinement, should reflect the predicted risk and severity of consequences
of GEO escape.
Because methods can fail, a single confinement method will not neces-
sarily prevent transgene escape. For most GEOs, their escape will not pose
a risk. In some cases, however, stringent confinement could be warranted,
which a single method would not provide. Redundancy involves applying
two or more types of safety measures to product design and use, each with
fundamentally different strengths and possible vulnerabilities, so that the
failure of one safety measure would be countered by the integrity of another.
The choice of redundant confinement techniques, including bioconfinement,
should consider a list of methods whose characteristics will combine to
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EXECUTIVE SUMMARY 9
produce the best results. In many cases, this will involve the application of
a mix of biological, physical, and physicochemical confinement measures
tailored to specific GEOs. In other cases, it may be possible to combine two
barriers of the same type but whose failures would be independent events,
such that a failure of one barrier does not trigger a failure of the other.
· It is unlikely that 100% confinement will be achieved by a single
method.
· Redundancy in confinement methods decreases the probability of
failing to attain the desired confinement level.
The development, testing, and use of GEOs is increasing worldwide.
GEOs can move across national borders by a variety of mechanisms includ-
ing natural phenomena and trade. No country can manage all of the
confinement issues that could affect its environment. An assessment of
bioconfinement in any country will require attention to the efficacy of a
given method and to concerns about its likely consequencesnot just within
that country but in other places as well.
· Regulators should consider the potential effects that a failure of
GEO confinement could have on other nations, as well as how foreign
confinement failures could affect the United States.
· International cooperation should be pursued to adequately manage
confinement of GEOs.
A bioconfinement scheme will be effective only if it is fully imple-
mented, and several factors affect compliance. The efficacy of bioconfine-
ment will vary with the human processes involved in applying the technique;
the confinement method itself; the characteristics of the GEO; the cost of
compliance; the characteristics of the organizations involved; the regulatory
system in place; and public transparency.
The majority of the bioconfinement methods discussed in this report
are in development and have not been used in conjunction with commer-
cially available GEOs. Consequently, the public has had little opportunity
to develop opinions regarding this aspect of biotechnology. Nonetheless,
GEOs or their products can have social significance or be infused with
symbolic, social, and aesthetic values that might present important challenges
for determining the need for or application of bioconfinement methods. In
order to enhance public trust and acceptance of a given confinement strat-
egy for a GEO, a sound science-based risk assessment might need to be
coupled with a clear and public articulation of any potential ethical
concerns.
Broad social and ethical values should be considered in assessing the
stringency of the integrated confinement system which includes bio-
confinement.
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10 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS
The public's right to informationoften called transparencyand its
right to participate in decision making are fundamental to the practice of
democracy. Each right complements the other. Appropriate transparency
and public participation can improve the effectiveness of confinement, for
example, by informing decision makers about otherwise unknown facts
about the environments in which confinement would be implemented, and
can increase the acceptance of bioconfinement measures (and of the GEOs
being confined) by building trust in the decision-making process.
Transparency and public participation should be important compo-
nents in developing and implementing the most appropriate bioconfinement
techniques and approaches.
DETECTING AND MITIGATING BIOCONFINEMENT FAILURE
Failures in the bioconfinement of GEOs have not been documented to
date, in part because so few methods have been implemented. However,
given the imperfections of methods under development and those of methods
that have been applied to nonengineered species, it is likely that failure will
occur. The degree to which failed confinement events can be monitored and
managed depends on whether the GEOs are easily detected, the scale at
which they are released into the environment, the GEOs' subsequent popu-
lation dynamics, and the degree to which they can hybridize with related
species. Early detection of failed methods will be important for mitigating
bioconfinement failure, especially if the confined transgenes are likely to
spread. Even if a failure is detected early, effective mitigation might not be
feasible.
Some limited options are available for detecting individuals and culling
them after failed bioconfinement. In plants, a failure might be signaled by a
distinctive phenotypic trait, such as the presence of flowers on plants that
have been engineered to lack them, so workers could cull abnormal plants
from small fields. The failure of many bioconfinement methods, however,
will be much more difficult to detect. For example, elaborate experiments
would be needed to determine whether a repressible seed-lethal transgene is
functioning properly. Also, many bioconfined plants will be grown on such
large areas of land that repeated comprehensive inspections will be imprac-
tical. In the future, DNA "fingerprints" could be linked to bioconfined
transgenes to function as "bio-barcodes" that could be detected and used to
cull GEOs. Remote sensing approaches might also be available to detect
GEOs.
It is feasible to detect and then cull individual fish in which triploid
sterilization induction fails before they are transferred from secure hatcheries
to much less secure facilities, such as outdoor ponds or open-water cages.
Economies of scale and possible automation could reduce the cost of such
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EXECUTIVE SUMMARY 11
efforts. A similar approach can be applied to oysters and shrimp. To detect
and cull failures in bioconfinement of fish, shellfish, or insects, one could
screen for proteins expressed by the key gene involved or for a co-inserted
marker gene. Nonlethal detection might be possible for larger organisms or
with such marker genes as green fluorescent protein; detection in smaller
organismsespecially insectswould be more likely to require lethal sam-
pling. It is not currently possible to detect or cull microbes if bioconfinement
fails. The committee did not speculate about cost-effectiveness because
genetic engineering-based bioconfinement methods are theoretical or at an
early stage of development.
Current methods for detecting and culling individual GEOs after a
bioconfinement failure are very limited, and they depend on the organism
and scale of the original release of the GEO.
For large-scale GEO releases, effective monitoring will be essential for
mitigating failure. Currently, monitoring is difficult because it involves
searching for what often will be a rare event over a potentially large area. In
the future, organisms might be purposefully transformed with additional
constructs for monitoring. Ideally, monitoring methods would be devel-
oped that could identify escapes with remote sensing. Monitoring should be
seen as a complement to confinementnot a replacement for it. That is, the
act of monitoring should not result in complacency about the possibility of
a bioconfinement failure.
Easily identifiable markers, sampling strategies, and methods should be
developed to facilitate monitoring of bioconfined GEOs in the environment.
ECOLOGICAL CONSEQUENCES OF LARGE-SCALE
USE OF BIOCONFINEMENT
Many bioconfinement methods might be successfully used and result in
certain GEOs having negligible effects on wild populations, biological com-
munities, or ecosystems, but there has been little research on this topic.
Some methods have been used in nonengineered organisms in the past,
often with other goals, and they were considered in the committee's evalu-
ation. Those methods include growing male-sterile crops for hybrid seed
production, small-scale rearing of sterile fish, and releasing sterile male
insects that mate with wild females as part of biocontrol strategies to reduce
pest insect populations.
Two related areas of ecological concern about the use of bioconfinement
with GEOs were identified: the large scale at which bioconfined organisms
could be released and the possibility that even carefully planned, integrated
bioconfinement methods could fail. In some cases, the area over which
sterile or handicapped GEOs are released could be large enough to affect
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12 BIOCONFINEMENT OF GENETICALLY ENGINEERED ORGANISMS
biodiversity. In salmon and other species, the presence of large numbers of
sterile GEOs or those with reduced fitness in some cases could threaten
local biodiversity. There is concern that some native populations of animals
might lose the ability to compete for food or mate successfully in the
presence of more competitive or more attractive, but sterile, GEOs. If this
were to occur in small populations, depressed levels of natural reproduction
could threaten the long-term survival of native genotypes. In other cases,
the large-scale release of sterile GEOs could have the beneficial effect of
alleviating existing problems, such as the loss of genetic diversity that can
occur when modernand often genetically uniformcrop plants (or hatchery-
raised fish) interbreed with rare wild relatives or locally adapted varieties.
A more general problem with all bioconfinement methods is that occa-
sionally they could break down, especially if they are intended to confine
millions of free-living individuals. Depending on the original reasons for
using bioconfinement, the ecological consequences could be serious. If a
bioconfined GEO can become a pathogen or an invasive species after the
breakdown of an Integrated Confinement System, the decision to release it
on a large scale should be scrutinized with extreme caution. If the reason
for using bioconfinement is mainly commercial, the ecological effects of
bioconfinement failure could be of no consequence. It is difficult to general-
ize about the ecological effects of large-scale releases of bioconfined GEOs,
and further research should address these questions in relation to specific
realistic conditions.
Research is needed to characterize potential ecological consequences of
bioconfinement methods and to develop methods and protocols for assess-
ing environmental effects should confinement fail.
CONCLUSIONS
The current lack of quality data and science is the single most signifi-
cant factor limiting our ability to assess effective bioconfinement methods.
In many cases GEOs will not require bioconfinement, but when they do the
need for bioconfinement should be evaluated case by case, considering
worst-case scenarios and the probability of their occurrence. The evalua-
tion of whether and how to confine a GEO should be an integral part of its
development, and the need for bioconfinement should be considered early
in the process. It is unlikely that any single bioconfinement technique will
be completely effective, and using multiple techniques with different
strengths and weaknesses will decrease the probability of failure. Further-
more, many bioconfinement techniques still are in the early stages of devel-
opment, and the possible unintended consequences of some bioconfinement
methods mean that some technologies will be unacceptable under certain
circumstances. Therefore, before a GEO is released, the techniques to be
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EXECUTIVE SUMMARY 13
used should be tested in a variety of appropriate environments and in
representative genotypes under development, and the reproductive biology
of the GEO should be understood relative to that of its progenitor. If a
bioconfinement method is applied, an integrated confinement system should
be put in place. Such a system must be supported by a rigorous and compre-
hensive regulatory regime empowered with inspection and enforcement.
Finally, in order to implement effective bioconfinement of GEOs, the
committee recommends support for additional scientific research that
· characterizes as completely as possible the potential ecological risks
and consequences of a failure in bioconfinement
· develops reliable, safe, and environmentally sound bioconfinement
methods, especially for GEOs used in pharmaceutical production
· designs methods for accurate assessment of the efficacy of bio-
confinement
· integrates the economic, legal, ethical, and social factors that might
influence the application and regulation of specific techniques
· models (using models that are calibrated and can be verified experi-
mentally) the dispersal biology of organisms targeted for genetic engineer-
ing and release, where sufficient information does not exist.
Interdisciplinary research will improve the future of biotechnology by
developing new confinement methods that minimize the potential for unin-
tended damage to human health and the environment. The success of these
efforts will do much to bolster public confidence in the continued growth,
development, and opportunities presented by biotechnology.
Representative terms from entire chapter:
genetically engineered
