As Gods in the Garden
In the day ye eat thereof, then your eyes shall be opened, and ye shall be as gods…
The previous chapter dealt with a narrow slice of biotechnology – its application to humans. This chapter deals with applications of the same technology to other living things.
Agricultural biotechnology is one of the oldest forms of high tech, going back at least 8,000 years. That, by current estimates, is when the breeding program began that eventually produced maize – the cereal Americans call “corn” – possibly from Teosinte, a plant most of us would describe as a weed. Similar programs of selective breeding are responsible for creating all of our major food plants.
Not only is the creation of genetically superior strains by random mutation and selective breeding an ancient technology, so is cloning. It has been known for a very long time that fruit trees do not breed true to seed. To prove it for yourself, remove the seeds from a golden delicious apple, plant them, wait ten or twenty years, and see what you get. The odds are overwhelmingly high that it will not be a golden delicious and moderately good that it will not be anything you would want to eat.
The solution is grafting. Once your little apple tree has its roots well grown, replace the top section of trunk with a piece of a branch cut from a golden delicious tree. If you do it right, the new wood grows onto the old; everything above the graft will be golden delicious, genetically speaking, including the apples. You have just produced a clone, an organism (at least most of an organism) that is genetically identical to another. Like Dolly, the cloned sheep, your cloned tree was created using cells from a mature organism.
To be even fancier, let your tree grow until it has a few little branches and then replace the end of one branch with a piece of wood from a golden delicious, a second with a piece from a Swaar (ugly but delicious), and a third with a bit from a lady apple (tiny, pretty, tasty). You now have that staple of plant catalogs, a three-in-one apple. You have also just employed, in your own backyard, a form of biotechnology that has been known at least since Roman times and is in large part responsible for the quality of fruit, grapes, and wine over the last few thousand years.
New Under the Sun
Modern agricultural biotech adds at least two new elements to the ancient technologies of selective breeding and grafting. One gives us the ability to do what we have been doing better. The other gives us the ability to do something almost entirely new.
The traditional way of breeding a better apple is to create a very large number of seeds, plant them all, let them all grow up, and see how they come out. If, by great good luck, one turns out to be a superior variety, it can be propagated thereafter by grafting. With enough expert knowledge the plant breeder can improve the odds a little by picking the right parents, choosing a pair of trees that there is some reason to hope might produce superior progeny, pollinating one with pollen from the other and using the resulting seeds. But it is still very much a gamble.
As our knowledge of genetics and our ability to manipulate genes improve, we may be able to do better than that. If we discover that particular sequences of genes are related to particular desirable traits, we can mix and match to produce trees – or grapevines, or tomato plants – with the traits we want. We will be doing the same thing we could have done with the old technologies, but in a lot fewer than 8,000 years.
An odder and more interesting possibility is to add to one species genes from another, producing transgenic plants. A famous – and commercially important – example uses Bacillus thuringiensis, or Bt, a bacterium that produces proteins poisonous to some insects but not to humans or other animals. Varieties of plants have been produced by adding to them the genes from the Bt bacterium responsible for manufacturing those proteins. Such plants produce, in effect, their own insecticide. Other transgenic plants are designed to be resistant to widely used herbicides, permitting a farmer to kill weeds without harming the crop.
The same technology can also be used to alter the final crop, producing peanuts or tomatoes with longer shelf life or sunflower oil that combines long shelf life with low levels of saturated fats and trans fats.1 It is also possible to insert genes into a plant (or animal) that result in its producing something unrelated to its normal crop. Examples include bacteria modified to produce insulin, a cow whose milk contains human milk proteins, and a sheep whose milk contains a clotting factor missing from the blood of hemophiliacs.
Insect-resistant plants permit us to grow crops at lower cost and with much less use of insecticides. Other applications of the technology increase crop yields, reduce costs, improve quality, and provide low cost ways of producing valuable pharmaceuticals, including some that cannot, at least so far, be produced in any other way. Yet the technology has been fiercely attacked; in some parts of the world, most notably Europe, agricultural applications are severely restricted. Why?
A Nest of Serpents?
Abu Hurairah (may Allah be pleased with him) reported that the Prophet (peace and blessings of Allah be upon him) said: “Allah, may He be exalted, says: ‘Who does more wrong than the one who tries to create something like My creation? Let him create a grain of wheat or a kernel of corn.’”
Reported by al-Bukhari, Fath al-Baari, 10/385
One reason is obvious – hostility to anything new, combined with a romanticized view of nature. Lots of people like the idea of “natural foods,” although practically nothing we eat is natural in the sense of not having been substantially altered by human activity. And we have the term “chemical” used pejoratively, despite the fact that everything we eat and everything we are made out of is a combination of chemicals. The same attitude shows up in the description of the products of agricultural biotech as “Frankenfoods.” The Muslim tradition quoted above reflects a religious version of this view: Creating living things is God’s business, not ours.2
This attitude is of considerable importance today; over the next decade or two, it may result in European consumers getting lower quality food at higher prices than they otherwise would. One reason that may happen is that European farmers are subsidized by their governments and protected from foreign competition by trade barriers. The more European consumers can be persuaded that foreign foods are evil and dangerous, the easier it is for European farmers to sell what they grow.
While irrational hostility may be important in the short run, it is likely to be less so in the long. There are large parts of the world where increasing agricultural output means fewer people going hungry, making symbolic issues of natural or unnatural unimportant by comparison. And over time, new things become old things. Contraception was widely viewed as unnatural, wicked, dirty, and sinful 100 years ago. In vitro fertilization met at first with considerable suspicion. Both are now widely accepted. From a point of view that goes beyond the next decade, the interesting question is whether there are any real problems associated with this sort of technology. The answer is almost certainly yes. These are powerful technologies, and powerful things can do damage as well as good. Consider a simple example.
Our common food plants were bred from preexisting wild plants. Many of the latter are still around and to some degree cross-fertile with their domesticated descendants. That means that genetic traits introduced into crop plants may find their way, as pollen blown in the wind, to related wild plants. Herbicide resistance is a useful feature in a crop plant. It is a considerable nuisance in a weed. How serious this sort of problem is depends on whether transgenically improved crop plants are grown near wild relatives, whether the modification is of benefit to weeds, and whether the modification makes the weed more of a problem for humans.
Consider a transgenic tomato designed for better flavor or longer shelf life. Even if there are related wild plants, those characteristics are of no particular use to them, so wild plants with those characteristics would have no advantage over wild plants without them and no more of a problem for farmers.
The same does not hold for resistance to herbicides. Suppose that weed beets grow near the fields containing sugar beets transgenically modified to make them resistant to herbicides. Weed beets that have had the good luck to acquire the genes for resistance will be more successful in that location than ones that have not – and more of a nuisance.
Can We Compete with Mother Nature?
Stepping back a moment, it is worth looking at the general argument for why such problems cannot exist and seeing why it is sometimes wrong. That argument starts with the observation that existing plants, including weeds, have been “designed” by Darwinian evolution for their own reproductive success. Our current biotechnology is a much more primitive design system than evolution; that is why we produce new crops not by designing the whole plant from scratch but by adding minor modifications to plants provided by nature. One might therefore expect that if a genetic characteristic that we could give a weed were useful, the weed would already have it.
There are two things wrong with that argument. The first is that evolution is slow. Weeds are adapted to their environment, but that environment has only recently included farmers spraying herbicides on them. So they are not adapted, or at least not yet very well adapted, to resist those herbicides. If we deliberately create crop plants resistant to specific herbicides and the resistance spreads to related weeds we provide an evolutionary shortcut, a way of generating resistant weeds substantially faster than nature would.
The second error in the argument is more complicated. Evolution works not by designing new organisms from scratch but by a series of small changes. The more simultaneous changes are required to make a feature work, the less likely it is to appear. Complicated structures – the standard example is the eye – are produced by a long series of changes, each of which provides the organism at least a small gain in reproductive success. Features that cannot be produced in that way are unlikely to be produced at all.3
Genetic engineering also works by small changes – introducing one gene from a bacterium into a variety of corn, for instance. But the available range of small changes is different. There may be some changes in an organism that result in greater reproductive success, hence would have been selected for by evolution, which can be produced by genetic engineering but are unlikely to come about naturally. The introduction of genes that code for a particular protein lethal to particular insect pests, genes borrowed from an entirely unrelated living creature, is an example. This is a subject we will return to in a later chapter, when we consider nanotechnology’s still more ambitious attempts to compete with natural design.4
The possibility that engineered genes will spread into wild populations and so produce improved weeds is one example of a class of issues raised by genetic technology. Others include the possibility of indirect ecological effects – improved weeds, or crop plants gone wild, that compete with other plants and so alter the whole interrelated system. They also include such unanticipated effects as crop plants designed to be lethal to insect pests turning out to also be lethal to harmless, perhaps beneficial, species of insects. I started with the case of transgenic weeds because I think that is the clearest case of a problem that is likely to happen, although not one likely to have catastrophic consequences. If, after all, weed beets become resistant to the farmers’ favorite herbicide, they can always switch to their second favorite, putting them back where they started, with an herbicide to which neither weeds nor crop is especially resistant.
I am more skeptical about the other examples, mostly because I am skeptical about the idea that nature is in a delicate balance likely to produce catastrophe if disturbed. The extinction of old species and the evolution of new is a process that has been going on for a very long time. But while I am skeptical about particular examples, I believe that they illustrate a real potential problem arising from technological change – probably the most serious problem.
The problem arises when actions taken by one person have substantial dispersed effects on many others. The reason it is a problem is that we have no adequate set of institutions to deal with such affects. Markets, property rights, and trade provide a very powerful set of tools for coordinating the activities of a multitude of individual actors. But their functioning requires some way of defining property rights such that most of the effect of my actions is born by me, my property, and some reasonably small and identifiable set of other people.
If there is no way of defining property rights that meets that requirement, we have a problem. The alternative institutions – courts, tort law, government regulation, intergovernmental negotiations, and the like – that we use to deal with that problem work very poorly. The more dispersed the effects, the worse they work. If technological changes result in making actions with such dispersed effects play a much larger role in our lives, if, for example, genetic engineering means that my engineered genes eventually show up in the weeds in your garden 1,000 miles away, we have a problem for which no known institutions provide a reasonably good solution. This is an issue I will return to in later chapters.
Technological Protection for Biotechnology
Back in Chapter 8, we considered the problem of protecting intellectual property in digital form in a world where reproducing it is cheap and easy. The same problem arises with agricultural biotechnology, where the product comes complete with its own copier. One possible solution is to use intellectual property law to prevent farmers from buying the genetically engineered crop once and producing their own seeds thereafter. That should work better for crops than for computer programs since infringement, if it occurs, happens on a large scale in large open spaces.
A different solution is technological protection, some way of selling the object that contains the intellectual property while preventing the purchaser from copying what it contains. In an older version of agricultural biotech, hybrid seed varieties, it happened automatically. A farmer bought hybrid seeds, planted them, harvested the crop. If he then replanted from what he had harvested, the result, thanks to the magic of sexual reproduction, would be a crop with varying characteristics, reflecting the random process determining which genes from each parent ended up in each seed. Such a crop was harder to deal with than the uniform crop from purchased hybrid seeds, so the seed company could sell him more seeds each year.
That does not work with those transgenic species that do not depend on controlled hybridization, species that grow sufficiently true to seed for the farmers’ purposes. To deal with that problem, researchers developed and patented a way of accomplishing the same objective artificially.
The obvious approach is to engineer a plant whose seeds will be sterile. There is, however, a small practical problem. In the case of hybrid crops, you fertilize variety A with variety B, produce lots of hybrid seed, and sell it. Producing a transgenic seed is a more difficult and elaborate process, involving a lot of trial and error on the way to getting a single success. If all you end up with is one seed, producing a plant whose seeds are themselves sterile, you are going to have a hard time paying for your laboratory.
The solution is to genetically engineer a seed that produces a plant whose seeds are fertile, but that can be modified, by the application of suitable chemicals, to produce a plant whose seeds are sterile. You grow enough generations of the plant to produce the amount of seed you want. You then treat that seed and sell it. Farmers grow it, get their crop, but cannot replant, because the seeds of the plants grown from the treated seed are sterile. Not only does the seed company get to retain control over its intellectual property, it also reduces the risk of accidentally producing superweeds, since the pollen blowing from the genetically engineered crop has been genetically engineered to produce sterile seeds.
Opponents of agricultural biotech, in a brilliant propaganda coup, dubbed the patented invention the “terminator gene.” They argued that keeping farmers from replanting from their own seed would convert them into serfs under the thumb of the seed companies. It was never made entirely clear whether they thought that all farmers growing hybrid seed were already serfs. Nor was it explained how giving farmers the option of either growing transgenic crops and buying seed each year or growing conventional crops and replanting their own seed made them worse off than if they had only the latter alternative.
More responsible critics pointed out possible undesirable side effects. Consider, for example, an ordinary field of cotton planted next to a field of genetically engineered cotton. Some of the ordinary cotton is pollinated by the engineered cotton, producing sterile seeds. The farmer tries to replant from his ordinary cotton, as he has every right to do – and gets a disappointingly low yield.
For the moment, it looks as though the opponents have won. Whether through bad arguments, good arguments, or clever propaganda – who, after all, wants to defend a terminator gene? – they appear to have persuaded the seed companies to abandon this particular approach to protecting their intellectual property.5 Will it stay abandoned? We will have to wait and see.
SATAN IN THE WINGS
We have spent some time now on possible unintended bad consequences of genetic engineering. There are also the intended ones – biological warfare using tailor-made diseases or, more modestly, tailor-made weeds. Here again it is worth taking a step back to think about the implications of evolutionary biology. It is a mistake to think of deadly diseases as enemies out to destroy us. A plague bacterium not only has nothing against you, it wishes you well, or would if it were capable of wishing. It is a parasite, you are a host, and the longer you live the better for it.
Lethal diseases are badly designed parasites. That is why a disease that is really deadly is typically new, either a new mutation, an old disease infecting a population that has not yet developed resistance, or a disease that has just jumped from one species to another and not yet adapted to the change. Given time, evolution works not only to make us less vulnerable to a lethal disease but to make the disease less lethal to us.6
Unfortunately, the creation of lethal diseases no longer is limited to nature. Several years ago, a team of scientists announced that they had succeeded in recreating the poliovirus – from scratch. The relevant technologies are improving rapidly, along with the general improvement in biotechnology. It may not be that long before someone who wants to start a new smallpox plague or target enemies with anthrax will need only a suitable set of tools for biosynthesis and a complete description of the organism.7
When a James Bond villain sets out to create a disease that will kill everyone but himself and his harem, he is not in competition with nature – nature, Darwinian evolution, is not trying to make lethal diseases. That makes it more likely that he will succeed, more likely that there are ways of making diseases more deadly than the ones produced by natural evolution. The question then becomes whether the technological progress that makes it easier to design killer diseases – ultimately, perhaps, in your basement – does or does not win out in the race with other technologies that make it easier to cure or prevent such diseases. This is a special case of an issue we will return to in the context of nanotechnology, which offers to provide potential bad guys with an even wider toolkit for mass murder and may or may not provide the rest of us with adequate tools to defend against them.
Killing Only the Right People
Biological warfare is a simple problem if you are a lunatic out to end the world, but, since the technological changes that are making it easier for them to create diseases are also making it easier for other people to protect against them, lunatics are unlikely to have sufficient competence or sufficient resources to do a good job of it. The more serious danger is from research projects, probably funded by governments, to produce diseases intended to kill only the “right” people. Achieving that objective raises some practical problems.
The easy case is the one that has already happened, several times over. If there is a disease that your population is already resistant to and the target population is not, exposing the target population to it can have drastic effects. The obvious example is the effect on the New World population of exposure to Old World diseases; some historians estimate mortality rates of over 90%.8 For the most part this particular form of biological warfare was an accident, although there seems to be at least one historical case of the deliberate spreading of smallpox among Canadian Indians reported in the correspondence of British officers. William McNeill argues, in Plagues and Peoples, that civilized populations – defined simply as ones with cities – have an automatic biowarfare advantage in their interactions with the uncivilized, since lethal diseases require a dense population9 in order not to kill themselves off in the process of killing their hosts. Hence dense populations will be carriers of, and resistant to, diseases new and lethal to more dispersed populations.
In the modern world, human mobility is too high and dense populations too common for that particular sort of selective plague to be a useful tool for those inclined to mass murder. There are, however, two modern variants that might work better. The obvious one is to develop a disease, develop a vaccine, vaccinate your own population, then release the disease; a prudent aggressor would probably want to disguise the vaccination program as designed against some natural hazard.
Another alternative, requiring a more advanced technology, would be to design a disease specific to victims with particular genetic characteristics, ones much more common in the target population than your own. That has the disadvantage that, given human genetic variability, it is likely to kill a good many of your own citizens. But one can imagine either a government willing to accept that cost or one that did not consider it a cost, on the theory that citizens too closely related to the enemy genetically might be politically unreliable. If that seems implausible, consider the treatment of Japanese-Americans by the United States during World War II.
Another possibility would be to target places rather than people. That might mean designing a disease that would spread easily in the physical environment of the enemy nation but not in your colder or warmer, moister or drier, environment. It might mean a disease designed to burn itself out after a certain number of generations, using a more sophisticated version of the terminator gene approach. Start it in the middle of the enemy country, shut down your airports and ports for a week to keep out travelers who might be carrying it, and with luck kill a large fraction of the enemy population while leaving their land and factories untouched for your use and your own population untouched.
Provided the disease doesn’t succeed, during its allotted generations, in evolving itself free of the terminator gene.
1 Marketers for nusun, a commercially important new variety of sunflower oil, however, make a point of the fact that it has desirable characteristics but was created by conventional, not transgenic, methods.
2 One issue particularly likely to raise such concerns is the introduction of human genes into other species, human or animal, to produce what might be described as chimeras. See a recent discussion of the issue and an entertaining student paper dealing with it, written for the seminar that produced this book.
4 It is sometimes suggested that one crucial difference between genetic engineering and evolution is that the former permits transgenic alterations – the insertion in the DNA of one species of genes from another. There is, however, some evidence that important evolutionary developments, including photosynthesis in multi-celled organisms, are due to natural transgenic alterations, possibly “engineered” by viruses. For one discussion, see Knoll, 2004.
6 McNeill, 1978, and Oldstone, 1998.
7 A 2005 piece on a
technology for constructing custom microbes, and another
from a different source. The risks of
genetic engineering at the hobbyist level, and threats from the professional
And, finally, the risk of the accidental creation of more dangerous disease strains--we, after all, are less skilled than evolution at designing parasites that do not kill their hosts--see.
9 Alternatively, a lethal disease can exist in an environment sufficiently warm and moist to permit survival for a considerable time outside of the host.