Clifford Brunk Brunk is a professor of
molecular biology in the organismic biology, ecology and evolution
department. His research interests include molecular evolution and
genomic analysis..
From our position in North America, it is hard to understand the
controversy that surrounds genetically modified organisms elsewhere
in the world. The passionate involvement and strident activism
about GMOs in Europe ranks with the concerns about “mad
cow” disease and foot-and-mouth disease.
The lack of controversy in North America is not due to any lack
of GMOs here; one-third of our major commercial crops including
corn, soybeans, cotton and potatoes are GMO varieties. The majority
of GMO development has occurred in North America, largely in
California.
This situation is reminiscent of the old saw, “If you can
keep your head, while those around you are losing theirs, you may
not fully appreciate the seriousness of the situation”. Is
this the case with GMOs? Or is it possible that we have a
less-developed moral and ethical sense than our European
brethren?
More likely, we have a different perspective. Clearly, the
controversy over GMOs has an emotional component as well as factual
aspects.
The term GMO generally refers to varieties of organisms (usually
of agricultural importance) whose genetic complement has been
modified by molecular biological techniques, including the
introduction of genes from different species.
Ironically, almost all of the crop species that we depend on for
food are the products of extensive and deliberate genetic
manipulation by humans over many thousands of years. Selective
breeding has changed the original species so dramatically that it
is hard to identify the ancestral variety.
An example is corn (maize, in most of the world). The ancestor
apparently was a tiny plant with only a few small kernels, a far
cry from the huge cobs crowded with large kernels common in our
current hybrid varieties.
In one sense, current GMOs are only the most recent versions of
an age-old process of human manipulation of species of agricultural
value. In another vein, our current GMOs are the product of
sophisticated molecular biological technology that permits the
specific directed movement of genes between species ““ a
process that is rare in nature.
Evaluating the potential threat and promise of GMOs requires
critical analysis of numerous factors in a broad context. GMOs are
a significant factor in high-tech agriculture right now. The
majority of GMOs have been developed by Agro-Business and depend
heavily on irrigation, synthetic fertilizer and massive energy
input.
These GMOs are for pecuniary gain in highly developed economies,
pure and simple. The effectiveness of GMOs within our current
global economic system is evidenced by their prevalence.
To be sure, some GMOs have been developed to increase food
production and improve health and nutrition in developing
countries, where securing an adequate nutritious diet is a constant
struggle for billions of people.
A classic GMO of this variety is “Golden Rice,”
which has been modified to provide improved growth characteristics,
better nutritional quality, and incorporates the precursors of
vitamin D to prevent disease.
Currently, more than a million children die annually from
diseases related to vitamin D deficiency. Development of these
types of GMOs, primarily by private and academic institutions,
presents one of the best hopes for improved health and quality of
life for a large fraction of the world’s people.
Whatever the motivation for the development and use of GMOs,
they have significant potential to provide additional high-quality
food for a human population that is rapidly approaching a size at
which the production of adequate food will be the paramount
concern.
About two years ago, the estimated human population of the earth
exceeded six billion. At the beginning of the 20th century, the
earth’s population was about 1.5 billion and some time in the
1960s, it passed three billion. At this rate, the population of the
earth would be expected to double, surpassing 12 billion, during
the lifetime of most current college students.
Limitations on arable land, available fresh water and
inexpensive energy make it very hard to imagine food production
sufficient to meet the demands of 12 billion people.
Curtailing the increase in the human population is a global
imperative. However, in addition, we will need all the ingenuity
humans can muster to meet the challenges of feeding an increasing
population and GMOs, for better or worse, will be a significant
part of the response to this challenge.
The potential hazards of GMOs are more fuzzy than their
benefits.
The introduction of foreign genes into food crops, carries a
potential of health hazard, probably most plausibly through
allergic reactions. However, it is hard to conceive of allergic
reactions induced by GMOs that are of the magnitude presented by
some natural foods such as peanuts, which can induce
life-threatening immune reactions in sensitive individuals.
Threats to the environment are also plausible. The transfer of
“resistance genes” from GMOs to weed species presents a
credible potential for the creation of “super weeds.”
Large acreages of GMO crops will undoubtedly create evolutionary
pressures leading to ecological change. This is always the case;
our use of antibiotics since World War II has dramatically altered
the microbial ecology and has led to a significant increase in
antibiotic resistant pathogens.
Although the hazards of GMOs may be difficult to predict
accurately, our previous experience with technological innovations
warn us to be wary.
For almost 50 years chlorofluorocarbons were considered a major
triumph of the chemical industry and human ingenuity. Today, we
recognize CFCs as a major “greenhouse” gas and a
destroyer of the protective ozone shield in our upper
atmosphere.
A desire to return to a simpler time in which human activity did
not so dramatically impact the global ecosystem is understandable,
but a return to a simpler time is precluded by the size of the
human population.
Today almost one-third of the protein nitrogen consumed by
humans is the product of synthetic fertilizers. Our dependence on
the products of human innovation is broadly manifest; we are
committed to the consequences of our innovations for better or
worse.
The controversy over GMOs is not unique; it is only symptomatic
of our current world. We are frequently faced with decisions of
enormous consequence that require more information and wisdom than
we possess.
In addition, we are encumbered by prejudices and traditions that
are often inappropriate to the current circumstance. The best we
can hope for are decisions that view our situation from the
broadest perspective with the best available knowledge and that are
as free of bias as possible.
Human ingenuity is an awesome force, full of promise and
potential threat.