Biology Reference
In-Depth Information
14.12 Permanent Releases of Genetically Modified Arthropods into
the Environment
Currently (2012), there are no guidelines for evaluating the risks of releasing
transgenic arthropods for
permanent
establishment in the environment in the
United States. Experience suggests that the probability that a “new” organism
will become established in a new environment is small. For example, even when
we are optimizing conditions to obtain establishment of natural enemies in clas-
sical biological control programs, only
≈
24% of the introduced species actually
establish. Historical examples of biological invasions of pests or of establishment
of classical biological control agents demonstrate a lack of predictability in such
releases (
Ehler 1990
).
Genetically modified arthropods could pose somewhat increased risk of per-
manent establishment over those posed by invasive species because they are
likely to be released in very large numbers and into appropriate environmen-
tal conditions; it is likely that most invasive species enter the new environment
in low numbers and may not invade optimal environments. Even so,
Williamson
(1992)
speculated that the greater the genetic novelty, the greater the possi-
bility of surprising results of invasive species. Because GMAs are “novel,” they
should be considered likely to provide surprises.
Analyses of potential risks associated with GMAs should include evaluation
of the survival, reproduction, and dispersal of the population and their effects
on other species in the community (
Table 14.7
). Questions also should be asked
about the inserted DNA, its stability, and its possible effect on other species
should the genetic material be transferred (
Tables 14.2, 14.7
). In the United
States, both state and federal regulatory agencies, including state departments
of agriculture and the U.S. Department of Agriculture, Animal and Plant Health
Inspection Service (USDA-APHIS), have to be consulted for permission to release
genetically modified agricultural pests and natural enemies of agricultural pests.
If the release occurs at a university, permission to release is required from the
campus biosafety committee. Questions about potential detrimental effects of
the genetically modified arthropods on threatened and endangered species
will be asked by state and federal agencies, including the U.S. Department of
Interior, Fish and Wildlife Service (
Young et al. 2000
),
(Figure 14.2)
.
14.12.1 Models to Predict?
Can we use models to predict the outcome of releases of GMAs in pest-
management programs? Many types of population and genetic models could be
used in attempts to predict what will happen when GMAs are released into the
