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  • From: John Schinnerer <JohnS@STLabs.com>
  • To: "'permaculture@listserv.oit.unc.edu'" <permaculture@listserv.oit.unc.edu>
  • Subject: "Terminator" explanation, in detail, for "lay people" (long, ~35K )
  • Date: Wed, 13 Jan 1999 09:17:27 -0800

Aloha,

FYI - information specific enough (with references, etc.) and yet
"non-technical" enough to be of use in informing "the general public"
(and hopefully policy-makers) about potential dangers in this patent...

John Schinnerer

-------------------------

>From <http://www.bio.indiana.edu/people/terminator.html>


How the Terminator terminates:

an explanation for the non-scientist of a remarkable patent for
killing second generation seeds of crop plants

by

Martha L. Crouch, Associate Professor of Biology
Indiana University
Bloomington, Indiana, USA
crouch@indiana.edu

This paper is one in a series of essays meant to stimulate and
inform discussion of the subject. The author invites readers to
correspond with her directly if they have comments or questions
about her interpretation of the Terminator patent.

revised edition©1998

an occasional paper of

The Edmonds Institute
20319-92nd Avenue West
Edmonds, Washington 98020
USA


published with the help of grants from:

The HKH Foundation
The Funding Exchange
C.S. Fund


Introduction

Genetically modified organisms (GMOs) have become a commercial reality
in
agriculture. For example, it is estimated that in 1998 over 18 million
acres
in the United States will be planted in Roundup Ready® soybeans, which
were
first introduced in 1996 (Horstmeier 1998). These soybeans are
engineered by
Monsanto Corporation to contain a bacterial gene that confers tolerance
to
the herbicide glyphosate, or Roundup® , also made by Monsanto. Only two
years after the introduction of Roundup Ready® soybeans, over 30% of the
corn and soybeans planted in the United States, and close to 50% of the
canola planted in Canada, have been genetically engineered to be either
herbicide or pesticide resistant.

Monsanto and the other companies that have invested heavily in
biotechnology
in the last two decades are starting to make some money after years of
promises without products, and they are aggressively protecting their
patented seeds. In a recent issue of the Farm Journal (Monsanto 1997),
Monsanto ran a full page advertisement asking farmers to respect the
company's property rights:

It takes millions of dollars and years of research to
develop the biotech crops that deliver superior value to
growers. And future investment in biotech research depends
on companies' ability to share in the added value created by
these crops. Consider what happens if growers save and
replant patented seed. First, there is less incentive for
all companies to invest in future technology, such as the
development of seeds with traits that produce
higher-yielding, higher-value and drought-tolerant
crops....In short, these few growers who save and replant
patented seed jeopardize the future availability of
innovative biotechnology for all growers. And that's not
fair to anyone.

In the future, companies and government breeders who genetically
engineer
crops may not have to ask for such compliance. If the procedure outlined
in
a recent patent comes to fruition and is widely used, plant variety
protection will be biologically built into the plants themselves.

In March of 1998, a seed company later to be purchased by Monsanto,
Delta
and Pine Land Company, in collaboration with the United States
Department of
Agriculture, was awarded U.S. Patent Number 5,723,765: Control of Plant
Gene
Expression. Although the patent is broad and covers many applications,
one
application favored by the patent's authors is a scheme to engineer
crops to
kill their own seeds in the second generation, thus making it impossible
for
farmers to save and replant seeds.

This "invention" has been dubbed the "Terminator Technology" by Rural
Advancement Foundation International (RAFI), and that group of
researchers
have analyzed some of the technology's serious social, economic and
environmental implications (RAFI 1998). However, many of the
consequences of
Terminator cannot be fully appreciated without an understanding of the
science behind the invention. In this paper, I outline the steps
involved in
engineering Terminator Technology into a specific crop. After explaining
the
process, I then discuss which details might have the devil in them.


Overview

To help describe the Terminator procedure, I have confined the
explanation
to only one of the many possibilities covered by the patent. The example
I
have chosen is cotton seed, which previously has been
genetically-engineered
with a unique trait, herbicide tolerance. In my discussion, I have
assumed
that to ensure that the descendants of the herbicide tolerant seeds are
not
used without compensation to the seed company, the company has
additionally
genetically engineered the cotton with Terminator. Although this is a
hypothetical case -- Terminator cotton is not yet on the market, after
all
-- all the components of the procedure have been shown to function, at
least
in the text of the patent for Terminator.

Cotton is not often sold as a hybrid seed, and is thus a likely
candidate
for Terminator protection. By way of contrast, corn is usually planted
as a
hybrid, and thus has some measure of variety protection already. This is
because the first generation of a hybrid is genetically fairly uniform,
and
has been bred to have desired characteristics that are not present in
either
parent alone. When these hybrids make seeds, however, the second
generation
is quite variable because of the shuffling of genes that occurs during
sexual reproduction. Industrial agriculture requires uniformity, because
the
plants must dovetail with mechanization. Therefore, industrial farmers
who
grow corn usually buy new seed every year.

There are several major crops which usually are not grown from hybrid
seeds.
These include wheat, rice, soybeans, and cotton. Farmers often save the
seeds from these crops, and may not go back to the seed company for
several
years--or longer, in some parts of the world-- to purchase a new
variety.

It would be a big boost to seed company profits if people who now grow
non-hybrid crops would have to buy new seed every year. This may have
been
the major incentive for developing the Terminator Technology.

There likely were other reasons for developing Terminator. One reason
may
relate to the way in which Terminator's effect differs from
hybridization.
When Terminator is used, the second generation is killed. With
hybridization, the second generation is variable, but alive; and any
genes
present in the hybrid will be present in the second generation, although
in
unpredictable combinations. Therefore, a plant breeder who wanted to use
the
genetic material from the hybrid in his or her own breeding program
could
retrieve it from these plants. With Terminator, the special genes, such
as
the herbicide tolerance of my example, would not be easily available for
use
by competitors.

Another reason sometimes cited for using Terminator in combination with
a
genetically-engineered variety is to keep the GMOs from "escaping" into
the
environment. Many critics of biotechnology cite problems with releasing
GMOs
into the wild, noting that their effects on ecosystems and their members
would be difficult to predict (Rissler and Mellon 1996). Having all of
the
second generation seeds die would circumvent this problem altogether.


Rough Sketch and Review

Terminator is a complicated process to understand and it helps to review
beforehand some of the basic information about how genes function during
the
life-cycle of a plant. Readers with a good grasp of molecular biology
may
want to skip the review section (A simplified version of basic
biological
processes) following the general description and proceed directly to the
details of the Terminator Technology.


General Description of Terminator in Cotton

In the cotton example, the goal is to develop a variety of cotton that
will
grow normally until the crop is almost mature . Then, and only then, a
toxin
will be produced in the (seed) embryos, specifically killing the entire
next
generation of seeds.

The system has three key components: 1. A gene for a toxin that will
kill
the seed late in development, but that will not kill any other part of
the
plant. 2. A method for allowing a plant breeder to grow several
generations
of cotton plants, already genetically-engineered to contain the
seed-specific toxin gene, without any seeds dying. This is required to
produce enough seeds to sell for farmers to plant. 3. A method for
activating the engineered seed-specific toxin gene after the farmer
plants
the seeds, so that the farmer's second generation will be killed.

These three tasks are accomplished by engineering a series of genes,
which
are all transferred permanently to the plant, so that they are passed on
via
the normal reproduction of the plant.


A simplified version of basic biological processes

A plant starts life as a single cell, an egg that has been fertilized by
sperm which has been delivered to the egg by the pollen. This first cell
divides many times to form the tissues and organs characteristic of the
species. The process of going from a single cell to an adult is called
development. As development proceeds, cells become different from each
other
and change. Cells in the leaf become distinct from cells in the root,
for
example. Most of the differences can be attributed to changes in the
kinds
and amounts of proteins made in the cells, because many of the
structures in
cells are made of proteins, and most of the processes that occur are
influenced by enzymes, which are also proteins. Thus, scientists who
study
development spend a lot of effort describing protein patterns.

By studying which proteins are present in different tissues and organs,
biologists have learned that each cell has several thousand different
proteins, but most of the proteins are very rare in the cell. A few
hundred
proteins may be moderately abundant, and a few may be quite abundant.
Also,
some proteins are found in all kinds of cells and at all times in
development, whereas other proteins are only present in a particular
tissue,
or at a specific time. For example, the gluten proteins responsible for
the
elasticity of bread dough are found only in the seed,and are present
there
in very large amounts. In contrast, the enzyme that splits glucose as a
first step in releasing energy is found in all living cells, but in
fairly
small amounts.

Some proteins are made in response to environmental changes, such as
increases in temperature, and thus may or may not be present during the
life
of a particular plant.

The most common way for a cell to control how much of which kinds of
proteins are present is to control which genes are functioning
(Rosenfeld et
al. 1983). Proteins are chains of different amino acids, and the order
of
amino acids and the length of the chain are unique for each kind of
protein.
Each unique amino acid sequence is specified by a code on a chromosome
in
the cell's nucleus. The code is made of DNA. For the purposes of this
discussion, a gene is a piece of DNA that contains the code for a
specific
protein. Genes are present in specific places along the length of the
chromosomes.

It turns out that just about every cell has two full sets of genes (one
set
of chromosomes from the sperm and one from the egg), which code for the
proteins made in all of the tissues and organs that an individual plant
will
need during its life cycle. However, only those genes whose proteins are
needed in a particular cell will be used by that cell. These are the
active
genes. The other genes just sit there on the chromosomes, inactive in
that
cell, but active somewhere else in the plant.

Whether a gene is active or not depends on complex interactions between
the
DNA and other molecules in the cell. Specifically, a typical gene can be
divided into parts. The first part is a stretch of DNA responsible for
interacting with the cell or the environment, and is called the
promoter.
The second part actually contains the code for the order of amino acids
in
the protein, and is called the coding sequence. When the gene is active,
the
promoter is interacting with other molecules in a way that allows the
coding
sequence to direct the synthesis of a specific protein (through a
complex
set of steps).

Genetic engineering can be defined as the process of manipulating the
pattern of proteins in an organism by altering genes. Either new genes
are
added, or existing genes are changed so that they are made at different
times or in different amounts.

Because the genetic code is similar in all species, genes taken from a
mouse
can function in a corn plant; and so on. Also, promoters from one coding
sequence can be removed and placed in front of another coding sequence
to
change when or where the protein is made. For example, when the promoter
for
casein, the major protein in milk, is removed and put in front of the
coding
sequence for human growth hormone, it causes human growth hormone to be
made
in cow's milk instead of casein. Of course, in order to make human
growth
hormone in cow's milk, the engineered gene has to be incorporated into
the
genetic material of the cow. There are many ways to do this. I will not
go
into the details here.

The general process of moving genes between species is called
transformation, and the result is a transgenic organism. Lately,
transgenic
organisms are being called genetically modified organisms, or GMOs.


Details of the Terminator technology

The key to Terminator is the ability to make a lot of a toxin that will
kill
cells, and to confine that toxin to seeds.

To accomplish this, in the case of our cotton example, the plan is to
take
the promoter from a gene normally activated late in seed development in
cotton, and to fuse that promoter to the coding sequence for a protein
that
will kill an embryo going through the last stages of development.

In the Terminator patent, the authors use a promoter from a cotton LEA
(Late
Embryogenesis Abundant) gene. This gene is one of the last to be
activated.
Its protein is not made until the seed is full-sized, has accumulated
most
of its storage oil and protein and is drying down in preparation for the
dormant period in between leaving the parent plant and germinating in
the
soil. If the engineered gene has the same pattern of expression,
LEA-promoter-directed proteins should be made in high quantities, only
in
seeds, and late in development. It is important for the cotton seeds to
go
through most of their growth before the toxin acts, because the cotton
fiber
is an outgrowth of the seed coat and is made as the cotton develops.
Further, after the cotton fibers are removed (for human use), the seed
is
then crushed for oil and protein, both of which are eaten by people and
livestock. The cotton crop would be of little use to a farmer if the
seeds
did not mature normally before dying.

As for a toxin, there are several possibilities discussed in the patent,
but
the patent authors recommend a ribosome inhibitor protein (RIP) from the
plant Saponaria officinalis. This protein works is small quantities to
stop
the synthesis of all proteins. Since cells need proteins for almost
everything, they die fairly quickly when they can't make proteins.
According
to the patent, the RIP is non-toxic to organisms other than plants.

The manipulations of DNA required to engineer a seed-specific
promoter/toxin
coding sequence gene are done in test-tubes and bacteria, and then the
altered gene is put into a cotton plant, using one of several possible
well-established methods.

However, this is not all there is to it. It this were all, then as soon
as
the transgenic plant went through its life cycle and came around to seed
development, that would be the end of the project. There would soon be
no
viable seeds to sell to farmers.

The Terminator patent offers an ingenious method for keeping the toxin
gene
from being active until long after the farmers plant their crops. The
trick
is accomplished by inserting a piece of DNA in between the seed-specific
promoter and the toxin coding sequence that blocks it from being used to
make protein.

At either end of the blocking DNA are put special DNA pieces that can be
recognized by a particular enzyme, such as the enzyme called
recombinase.
Whenever the recombinase encounters these DNA pieces, the DNA is cut
precisely at the outside of each piece, and the cut ends of the DNA fuse
together, with the result that the blocking DNA is removed. When this
happens, the seed-specific promoter is right next to the toxin coding
sequence, and is able to function in making the toxin. But this does not
happen immediately. Toxin will not be produced until the end of the next
round of seed development, because that is when the LEA promoter is
active.

Thus, after the recombinase enzyme does its work, the plant grows
normally
from germination, through growth of stems, leaves, roots, and all the
way
through flower formation, pollination and most of seed development.
Then, on
cue, the seeds die.

All this accomplished, there remains one more problem: How to grow
several
generations of the genetically-engineered variety so that its seed can
be
multiplied to sell to farmers?

The Terminator patent solves the dilemma by preventing recombinase from
acting until just before the farmers plant their seeds. The patent
holders
give several possible ways to do this, but concentrate on the following
procedure: They propose putting a recombinase coding sequence next to a
promoter that is always active -- in all cells, at all times -- but that
is
repressed. The promoter can be made active again -- derepressed -- by a
chemical treatment. Therefore, the seed sellers can treat the seeds
right
before planting, thus allowing the recombinase to be made then, but not
before.

One of the repressible promoter systems they discuss in detail is
controlled
by the antibiotic tetracycline. A gene that makes a repressor protein
all of
the time would be put into the cotton plant, along with a recombinase
gene
that has a promoter engineered to be inactivated by the repressor
protein.
Under most conditions, then, the repressor would interact with the
recombinase gene; no recombinase would be made; the toxin gene would be
blocked; and no toxin would be made, even during seed development when
the
LEA promoter normally would be active.

To activate the toxin gene, seeds just starting to germinate would be
treated with tetracycline, right before they are sold to farmers. The
tetracycline would interact with the repressor protein, keeping it from
interfering with production of recombinase. Recombinase would be made,
cutting out the blocking DNA from the toxin gene. The toxin gene would
now
be capable of making toxin, but would not actually do so until the end
of
seed development. The next generation would thus be killed.

To accomplish the Terminator effect in cotton, then, three engineered
components must all be transferred into a cotton plant's DNA:

1. a toxin gene controlled by a seed-specific promoter, but blocked by a
piece of DNA in between the promoter and the coding sequence;

2. a repressor protein coding sequence with a promoter that is active
all of
the time; and

3. a recombinase coding sequence, controlled by a promoter that would be
active at all times, except that it is also regulated by repressor
protein,
which can be overridden with tetracycline.

The actual transfer of genes into the plant is not a very precise
operation.
Any one of a variety of methods can be used: the genetically-engineered
DNA
can be injected into the nucleus of a cotton cell with a tiny needle, or
plants cells can be soaked in the DNA and electrically shocked, or the
DNA
can be attached to small metal particles and shot into the cells with a
gun,
or viruses and bacteria can be engineered to infect cells with the DNA.
In
all cases, the genetically-engineered DNA has to find its way to the
nucleus, and become incorporated into the plant chromosomes. The number
of
copies of the inserted genes and their locations on the plant
chromosomes
are unpredictable, and how well the new genes will function hangs in the
balance.

It takes a lot of effort to locate cells that have incorporated DNA in
significant amounts and in locations that work. Basically, whole plants
have
to be regenerated from the cells or tissues that were transformed with
the
foreign DNA, and then each plant has to be tested for the presence and
function of the new genes.

After plants with well-functioning new genes are identified, they are
then
mated in combinations that result in a line of cotton where both sets of
chromosomes (in all of the offspring) have all the components necessary
for
Terminator to function. These plants are mated together to make a large
quantity of seed for sale.

In effect, Terminator Technology gives the seed producer the ability to
determine when to set Terminator in motion. Until the recombinase is
made,
the cotton plants grow normally. After recombinase is made, the second
generation of seeds is killed, protecting the patented variety.


Some problems that may crop up with the use of Terminator

The patent on this technology is complex. I have described only one of
many
possible applications of the procedure. Clearly, one cannot determine
ahead
of time all possible biological ramifications of implementing the
patent.
However, potential problems have already been noted (Ho 1998). I deal
with
some of them below.

Will the Terminator spread to other plants?

It is likely that Terminator will kill the seeds of neighboring plants
of
the same species, under certain conditions. However, the effects will be
confined to the first generation, and will not be able to spread to
other
generations. The scenario might go like this: when farmers plant the
Terminator seeds, the seeds already will have been treated with
tetracycline, and thus the recombinase will have acted, and the toxin
coding
sequence will be next to the seed-specific promoter, and will be ready
to
act when the end of seed development comes around. The seeds will grow
into
plants, and make pollen. Every pollen grain will carry a ready-to-act
toxin
gene. If the Terminator crop is next to a field planted in a normal
variety,
and pollen is taken by insects or the wind to that field, any eggs
fertilized by the Terminator pollen will now have one toxin gene. It
will be
activated late in that seed's development, and the seed will die.
However,
it is unlikely that the person growing the normal variety will be able
to
tell, because the seed will probably look normal. Only when that seed is
planted, and doesn't germinate, will the change become apparent.

In most cases, the toxin gene will not be passed on any further, because
dead plants don't reproduce. However, under certain conditions I will
discuss later, it is possible for the toxin gene to be inherited.

In any case, dead seeds, where they occur, would be a serious problem
for
the farmer whose fields are close to the Terminator crop. How many seeds
die
will depend on the degree of cross-pollination, and that is influenced
by
the species of plant, the variety of crop, weather conditions, how close
the
fields are to each other, and so on. If many seeds die, it will make
saving
seed untenable for the adjacent farmer. Even if only a few seeds die,
they
will contain the toxin and any other proteins engineered into the
Terminator-protected variety. These new "components" may make the seed
unusable for certain purposes.


Will seeds containing the toxin made by Terminator be safe to eat?

In fact, the effects of the toxin on the uses of the seed are a serious
question. This issue is discussed in the patent at the end of page 8.
There
the authors say that "[i]n cotton that would be grown commercially only
selected lethal genes could be used since these proteins could impact
the
final quality of seeds....If the seed is not a factor in the commercial
value of a crop (e.g., in forage crops, ornamentals or plants grown for
the
floral industry) any lethal gene should be acceptable."

This is dangerously reductionist thinking, because people are not the
only
organisms that interact with seeds. In forage crops, for example, not
all of
the forage is always harvested before seeds are mature, depending on
conditions. How will a particular toxin affect birds, insects, fungi and
bacteria that eat or infect the seeds? If a forage crop with toxin-laden
seeds is left in the field, and the seeds come in contact with the soil,
how
will that affect the ecology of soil organisms? These are important
questions because a variety of specific organisms are necessary for the
healthy growth of plants. Further, a floral or ornamental crop with
Terminator may happen to grow near a related crop where the seeds are
used,
and if pollination occurs, the seeds will contain toxin without that
farmer
knowing. The toxin could end up in products without anyone's knowledge.
For
example, an ornamental sunflower could spread Terminator to an oilseed
variety, and then the toxin could end up in edible oil or in sunflower
seed
meal.

Other potential problems with making novel toxins in edible seeds have
to do
with allergenicity. The RIP toxin described earlier may not be directly
poisonous to animals, but may cause allergic reactions. If the seeds are
being mixed with the general food supply, it will be difficult to trace
this
sort of effect.


Will dead seeds have different properties than living seeds?

Although Terminator is supposed to kill seeds very late in development,
it
is not known what other effects, if any, Terminator may have. Will the
dead
seeds be more or less easy to store? Perhaps they will respond
differently
to changes in humidity, or to infection with bacteria and fungi. If dead
seeds do behave differently, even a few "bad apples may spoil the
barrel",
and the problem of partial killing of neighbors' crops may be even more
of
an issue.

There also may be nutritional changes in seeds that are killed late in
development. Although most of their oils and proteins are present, it is
possible that seeds will start to deteriorate or will lack some minor
component that is important. The functional properties of specific
molecules
in foods, for example, are just beginning to be appreciated and are
likely
to play important roles in preventing diseases. These possibilities
require
further study.


Will the use of an antibiotic to treat seeds before planting be a
problem?

If seed companies do indeed use tetracycline to set the cascade of
toxin-gene activation in motion, then they will have to soak a very
large
amount of seed in the antibiotic. Basically, every seed planted by the
farmer will have to be so treated. How many pounds of cotton seed or
wheat
seed are needed to plant an acre, and how many acres will be put in? In
fact, I am having trouble visualizing exactly how this will work,
because
the seeds must be treated with tetracycline after they have matured
completely (so that the toxin won't be made in the first generation),
but
before planting (otherwise, the farmer would have to apply antibiotic to
the
plants). Handling seed that has been soaked seems like a tricky process
to
me, but perhaps there are viable methods. At any rate, even at low
concentrations there will be a lot of tetracycline to handle and dispose
of,
and large-scale agricultural uses of antibiotics are already seen as a
threat to their medical uses. Further, the increased tolerance of
bacteria,
residual or waste antibiotics may also have a harmful effect on soil
ecology.

Again, I am dismayed by the reductionist tone of the discussion of these
issues in the patent. On page 7, line 30, the authors state that "since
tetracycline has no harmful effects on plants or animals, its presence
would
not otherwise impede normal development of the plant, and residual
amounts
left on the seed or plant after treatment would have no significant
environmental impact." Although it is true that tetracycline has no
direct
effect on animals, such as humans, the indirect effects can be severe.
This
is because we depend on a myriad of interactions with microorganisms for
our
daily functioning, from proper digestion to protection from pathogens.
The
patient information sheet that comes with any prescription for
tetracycline
is convincing evidence that tetracycline is not harmless to use.

Plants too depend on microorganisms. They do not function normally
without a
web of interactions, and indirect effects from substances like
tetracycline
may prove to be important.


Will Terminator prevent genetically modified organisms from
escaping?

Clearly, farmers would not want plants genetically modified with
Terminator
to spread into surrounding areas or to grow from seed as unexpected
"volunteers" in another season. They also would not want the Terminator
plants to exchange genes with other varieties or related species.
Interestingly, Terminator has been proposed as a method to prevent just
such
escapes of GMOs and their genes. However, Terminator is not likely to
function well for such purposes.

First, it is unlikely that any tetracycline treatment will be 100%
effective. For various reasons, some seeds may not respond, or take up
enough tetracycline to activate recombinase. In such cases, the plants
growing from the unaffected seeds would look just like all the others,
but
would grow up to make pollen carrying a non-functional toxin gene. The
pollen would also carry the genetically-engineered protein supposedly
being
protected by Terminator, such as herbicide-tolerance. If this pollen
fertilized a normal plant, the seed would not die, because no toxin
would be
made, but the seed would now have the herbicide-tolerance gene and could
pass that on. Thus a trait from the GMO would have escaped through the
pollen.

Of course, self-fertilized seeds of the Terminator line would also
survive
in the second generation, if the tetracycline treatment failed, and
could be
carried off by birds, or grow as "volunteers" the next season.

Another possibility is that even successfully activated Terminator genes
may
fail to make toxin because of a phenomenon called gene silencing. In
experiments with other GMOs, it was discovered - quite unexpectedly -
that
in some cases, previously active (introduced) genes can suddenly stop
working. If this phenomenon occurred with seeds containing the
Terminator
gene, plants containing the silenced toxin gene could grow and
reproduce,
perhaps for several generations. Thus, Terminator and other engineered
genes
could be carried into the future, to be expressed -- perhaps still
unexpectedly -- at some later time.

Depending on Terminator to prevent GMOs or their traits from spreading
unintentionally is unrealistic. "Escapes" are even more likely to occur
in
some of the other patent applications, where the genetic components of
Terminator will reshuffle during sexual reproduction, and a portion of
the
seeds will lack the toxin altogether, and thus be viable.


Organisms are always changing; will Terminator mutate and change
characteristics is some dangerous way?

If plants were to carry silenced toxin genes, as described above, those
genes might suddenly be activated again, causing seeds to die
unpredictably
in subsequent generations. By the time the phenomenon occured, however,
it
might be difficult to ascribe the cause to Terminator.

Another possibility is that the Terminator may be activated at a
different
time or place in the plant. Fortunately, such events will be
self-limiting,
because the plants will die. However, for farmers, the instability and
unpredictability of GMOs has already been an economic problem. Genes
have an
ecology--a complex way of interacting with themselves and the
environment--that can interfere with the simple linear logic of genetic
engineering. A recent article in the Ecologist discussed this problem in
detail (Ho et al. 1998).


Final thoughts

These are a few of the potential snags that I see in the use of
Terminator
Technology. My analysis was based on the details of only one of the
applications described in the Terminator patent. I am confident that
some of
the particular problems I have discussed will be addressed by the seed
industry before they implement the technology. However, I am also sure
that
there will be other problems noone yet foresees or imagines. There will
be
surprises. But whatever the potential biological problems presented by
Terminator, in my view they are small in comparison to Terminator's
economic, social, and political ramifications (See RAFI 1998).


References

Ho, Mae-Wan, 1998. Genetic Engineering: Dream or Nightmare? The Brave
New
World of Bad Science and Big Business. Gateway Books, Bath, UK.

Ho, Mae-Wan, Hartmut Meyer and Joe Cummins, 1998. The biotechnology
bubble.
The Ecologist 28, pp. 146-153.

Horstmeier, Greg D., 1998. Lessons from year one: experience changes how
farmers will grow Roundup Ready beans in '98. Farm Journal, January
1998, p.
16.

Monsanto Advertisement, 1997. Farm Journal, November 1997, B-25.

RAFI-Rural Advancement Foundation International, 1998. This organization
has
written several press releases, communiques, and articles on Terminator
Technology. These can be accessed at RAFI's web site at
http://www.rafi.ca,
or by writing to RAFI, 110 Osborne St., Suite 202, Winnipeg MB R3L 1Y5,
Canada.

Rissler, Jane and Margaret Mellon, 1996. The Ecological Risks of
Engineered
Crops. The MIT Press, Cambridge, Massachusetts, US.

Rosenfield, Israel, Edward Ziff and Borin Van Loon, 1983. DNA for
Beginners.
Writers and Readers, US.

United States Patent Number 5,723,765: Control of Plant Gene Expression,
issued on March 3, 1998 to Delta and Pine Land Co. and The United States
Department of Agriculture. Inventors: M.J. Oliver, J.E. Quisenberry,
N.L.G.
Trolinder, and D.L. Keim.





  • "Terminator" explanation, in detail, for "lay people" (long, ~35K ), John Schinnerer, 01/13/1999

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