Monday, July 4, 2016
Is It Nice to Fool Mother Nature?
From the research towards
the treatment of human genomic disorders spurred by systems like Crispr
(clustered regularly interspaced short palindromic repeats) – effectively
editing gene sequencing – to genetically modified organisms in commercial food
products (animals and plants), mankind’s medical-scientific community is
heavily focused on messing with genes. As the medical community addresses
genetic disorders, as old world medications are hitting walls –
antibiotic-resistant bacteria, for example – and as Malthusian population
growth increases demands on the food supply system, the expanding biotech focus
is on designing nano-particles and reengineering genes and gene sequencing.
Efficiency. Disease resistance. Fatter and juicier.
Those expressing
religious and moral outrage at messing with God’s/nature’s creations have
joined natural-foods skeptics in questioning this newfound scientific
proclivity. Mandating label disclosures on food products is a hot topic
worldwide. But while these moral and regulatory battles rage globally,
scientists are also looking to using genetic editing to cope with the migration
of disease-carrying insects into new, unprepared regions impacted by global
warming.
“A revolutionary
technology known as ‘gene drive,’ which for the first time gives humans the
power to alter or perhaps eliminate entire populations of organisms in the
wild, has stirred both excitement and fear since scientists proposed a means to
construct it two years ago.
“Scientists dream of
deploying gene drive, for example, to wipe out malaria-carrying mosquitoes that
cause the deaths of 300,000 African children each year, or invasive rodents
that damage island ecosystems. But some experts have warned that the technique could
lead to unforeseen harm to the environment. Some scientists have called on the
federal government to regulate it, and some environmental watchdogs have called
for a moratorium…
“‘The potential to reduce
human suffering and ecological damage demands scientific attention,’ said
Elizabeth Heitman, a medical ethicist at Vanderbilt University who helped lead
the committee. ‘Gene drive is a fascinating area of science that has promise if
we can study it appropriately.’” New York Times, June 8th. But, all the
expected science-fiction-themed television and feature productions
notwithstanding, there is a very big catch.
“[There] is not yet
enough evidence about the unintended consequences of gene drives to justify the
release of an organism that has been engineered to carry one. But the green
light for gene drive research from the influential group, scientists said,
would likely open the door to new funding and provide an impetus for
governments around the world to consider how it might be regulated and deployed.
“For centuries, people
have tinkered with the genetic makeup of living things whose survival and
reproduction are already largely under our control: pets, farm animals, crops
and assorted species of laboratory animals. With the advent of new gene-editing
tools like one called Crispr, there is even growing debate about modifying
human embryos with traits that could be passed on their descendants. But a gene
drive involves potentially transforming an entire wild species over a few
generations by modifying just a few individuals.
“Our ability to do that
has so far been stymied because any changes humans might make typically reduce
an organism’s ability to survive and reproduce in its natural habitat: natural
selection eliminates the altered genes.
“Gene drives overcome
this by ensuring that a particular gene is transmitted to all of an
individual’s offspring, rather than the usual half, even if that makes them
less fit. The phenomenon has long been known to exist in nature, and Crispr
provides an effective way to harness it. By encoding the Crispr editing system
itself into an organism’s DNA, scientists can cause a desired edit to reoccur
in each generation, ‘driving’ the trait through the wild population.” NY Times.
But species in the wild do not operate in a vacuum. They are often material
factors in fully-dependent natural eco-cycles around them. Take one element out
and prepare to find “unintended consequences” in the ecosystem… potentially
very bad consequences that might be irreversible.
The arrival of new
insects into unfamiliar environments, such as the ones spreading the Zika
virus, has increased pressure on governments to take important steps to stop
these bugs any way they can. Spraying toxic chemicals to kill insects appears
to be a non-starter based on the years of watching “unintended consequences”
from earlier efforts. DDT anyone? So applying gene modifying applications,
since there really aren’t yet the kinds of “bad reports” that accompany toxic
insect sprays, seems to be the easy button.
Even assuming a need to
regulate such efforts, who’s in charge? Who has to sign off? “United States
Food and Drug Administration has authority over animals that have been
engineered with foreign DNA under a rule that regards them as a type of drug.
But the report suggests that other agencies, like the Fish and Wildlife Service
or the Bureau of Land Management, might be seen to have a stake in the
ecological concerns at the heart of gene drive experiments.” NY Times.
The world is looking to
the United States for leadership in the modeling and testing regimes in this
evolving field. Computer simulations are capable of some pretty sophisticated
analyses, but the scientific community seems to agree that it should be
interdisciplinary panels of approved experts who should set the standards.
“Each potential use of
gene drive carries its own set of risks and benefits, the report says, and
should be assessed independently. Even modeling the ‘cascade of population
dynamics and evolutionary processes’ that would influence the ecological
effects, the report [from the National Academies of Sciences, Engineering and
Medicine (N.A.S.), a governmental advisory group] noted, requires far more
research. Risks include the possibility that a gene drive might jump to another
species for which it was not intended, or that the suppression of one
undesirable organism will lead to the emergence of another that is even worse.
“The group recommends
‘phased testing,’ which would include safeguards at each step before eventually
releasing organisms into the wild, but it also noted the new ethical challenges
posed by how to obtain consent from people whose environments might be affected
by such a release. ‘There are few avenues for such participation,’ the report
noted, ‘and insufficient guidance on how communities can and should take part.’
“Gene drives spread a
trait through a population by ensuring that it is passed to virtually all of an
individual’s offspring as it reproduces, rather than the usual half. In
laboratory experiments, the desired change has appeared in nearly 100 percent
of the offspring of flies and mosquitoes. So far, gene drive research has
focused largely on mosquitoes that transmit infectious diseases to humans. The
Bill and Melinda Gates Foundation, which helped pay for the N.A.S. report, has
spent some $40 million on a gene drive project aimed at eradicating the species
of mosquitoes that spread malaria.” NY Times.
But will governments,
including our own, feel the pressure to deploy these insect-restraints before the
safety valves are put into place? Think Brazil and the up-coming Olympics, for
example. Or Africa. What if the safety valves don’t work? What if a few strays
get released by mistake? Does the benefit outweigh the risk? How do you feel
about this trend?
I’m
Peter Dekom, and it does appear that genetic alternation techniques are going
to grow and find increasingly wider application… so the time to create clear
guidelines has to be immediate.
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