Biotechnology is a set of techniques by which human beings modify living things or use them as tools. In its modern form, biotechnology uses the techniques of molecular biology to understand and manipulate the basic building blocks of living things. The earliest biotechnology, however, was the selective breeding of plants and animals to improve their food value. This was followed in time by the use of yeast to make bread, wine, and beer. These early forms of biotechnology began about ten thousand years ago and lie at the basis of human cultural evolution from small bands of hunter-gatherers to large, settled communities, cities, and nations, giving rise, in turn, to writing and other technologies. It is doubtful that, at the outset, the first biotechnologists understood the effects of their actions, and so the reason for their persistence in pursuing, for example, selective breeding over the hundreds of generations necessary to show much advantage in food value, remains something of a mystery.
The world's historic religions emerged within the context of agriculture and primitive biotechnology, and as one might expect they are at home in that context, for instance through their affirmation of agricultural festivals. In addition, Christianity took the view that nature itself has a history, according to which, nature originally was a perfectly ordered garden, but as a result of human refusal to live within limits, nature was cursed or disordered by its creator. The curse makes nature at once historic, disordered, both friendly and hostile to human life, and open to improvement through human work. These effects fall especially on human agriculture and childbirth, both of which are focal areas of biotechnology.
By the time of Charles Darwin (1809–1882), plant and animal breeders were deliberate and highly successful in applying techniques of selective breeding to achieve specific, intended results. Darwin's theory of evolution is built in part on his observation of the ability of animal breeders to modify species. The work of human breeders helped Darwin see that species are variable, dynamic, and subject to change. Inspired by the success of intentional selective breeding, Darwin proposed his theory of natural selection, by which nature unintentionally acts something like a human breeder. Nature, however, uses environmental selection, which favors certain individuals over others in breeding. The theory of natural selection, of course, led to a profound shift in human consciousness about the fluidity of life, which in turn fueled modern biotechnology and its view that life may be improved. While Christianity struggled with other implications of Darwinism, it did not object to the prospect that human beings can modify nature, perhaps even human nature.
The emergence of modern biotechnology
In the twentieth century, as biologists refined Darwin's proposal and explored its relationship to genetics, plant breeders such as Luther Burbank (1849–1926) and Norman Borlaug (1914–) took selective breeding to new levels of success, significantly increasing the quality and quantity of basic food crops. But it was the late twentieth-century breakthroughs in molecular biology and genetic engineering that established the technological basis for modern biotechnology. The discovery that units of hereditary information, or genes, reside in cells in a long molecule called deoxyribonucleic acid (or DNA) led to an understanding of the structure of DNA and the technology to manipulate it. Biotechnology is no longer limited to the genes found in nature or to those that could be moved within a species by breeding. Bioengineers can move genes from one species to another, from bacteria to human beings, and they can modify them within organisms.
The discovery in 1953 of the structure of DNA by Francis Crick (b. 1916) and James Watson (b. 1928) is but one key step in the story of molecular biology. Within two decades, this discovery opened the pathway to the knowledge of the socalled genetic alphabet or code of chemical bases that carry genetic information, an understanding of the relationship between that code and the proteins that result from it, and the ability to modify these structures and processes (genetic engineering). The decade of the 1980s saw the first transgenic mammals, which are mammals engineered to carry a gene from other species and to transmit it to their offspring, as well as important advances in the ability to multiply copies of DNA (polymerase chain reaction or PCR). The Human Genome Project, an international effort begun around 1990 to detail the entire DNA information contained in human cells, sparked the development of bioinfomatics, the use of powerful computers to acquire, store, share, and sort genetic information. As a result, not only is a standard human DNA sequence fully known (published in February 2001), but it is now possible to determine the detailed code in any DNA strand quickly and cheaply, a development likely to have wide applications in medicine and beyond.
Biotechnology is also dependent upon embryology and reproductive technology, a set of techniques by which animal reproduction is assisted or modified. These techniques were developed largely for agricultural purposes and include artificial insemination, in vitro fertilization, and other ways of manipulating embryos or the gametes that produce them. In 1978, the first in vitro human being was born, and new techniques are being added to what reproductive clinics can do to help women achieve pregnancy. These developments have been opposed by many Orthodox Christian and Roman Catholic theologians, by the Vatican, and by some Protestants, notably Paul Ramsey. Other faith traditions have generally accepted these technologies. In addition, some feminist scholars have criticized reproductive medicine as meeting the desires of men at the expense of women and their health.
Reproductive medicine, however it may be assessed on its own merits, does raise new concerns when it is joined with other forms of biotechnology, such as genetic testing and genetic engineering. In the 1990s, in vitro fertilization was joined with genetic testing, allowing physicians to work with couples at risk for a genetic disease by offering them the option of conceiving multiple embryos, screening them for disease before implantation, and implanting only those that were not likely to develop the disease. This technique, known as preimplantation diagnosis, is accepted as helpful by many Muslim, Jewish, and Protestant theologians, but is rejected by Orthodox Christians and in official Catholic statements. The ground for this objection is that the human embryo must be shown the respect due human life, all the more so because it is weak and vulnerable. It is permissible to treat the embryo as a patient, but not to harm it or discard it in order to treat infertility or to benefit another. The usual counterargument is to reject the view that the embryo should be respected as a human life or a person.
The significance of stem cells and cloning
Developments in cloning and in the science and technology of stem cells offer additional tools for biotechnology. In popular understanding, cloning is usually seen as a technique of reproduction, and of course it does have that potential. The birth of Dolly, the cloned sheep, announced in 1997, was a surprising achievement that suggests that any mammal, including human beings, can be created from a cell taken from a previously existing individual. Many who accept reproductive technology generally, including such techniques as in vitro fertilization, found themselves opposing human reproductive cloning, but they are not sure how to distinguish between the two in religiously or morally compelling ways. With few exceptions, however, religious institutions and leaders from all faith traditions have opposed human reproductive cloning, if only because the issues of safety seem insurmountable for the foreseeable future. At the same time, almost no one has addressed the religious or moral implications of the use of reproductive cloning for mammals other than human beings, although it has been suggested that it would not be wise or appropriate to use the technique to produce large herds of livestock for food because of the risk of a pathogen destroying the entire herd.
The technique used to create Dolly—the transfer of the nuclear DNA from an adult cell to an egg, thereby creating an embryo and starting it through its own developmental process—can serve purposes other than reproduction, and it is these other uses that are especially interesting to biotechnology. Of particular interest is the joining of the nuclear transfer technique with the use of embryonic stem cells to treat human disease. In 1998, researchers announced success in deriving human embryonic stem cells from donated embryos. These cells show promise for treating many diseases. Once derived, they seem to be capable of being cultured indefinitely, dividing and doubling in number about every thirty hours. As of 2002, researchers have some confidence that these cells can be implanted in the human body at the site of disease or injury, where they can proliferate and develop further, and thereby take up the function of cells that were destroyed or impaired.
Stem cells, of course, can be derived from sources other than the embryo, and research is underway to discover the promise of stem cells derived from alternative sources. There are two advantages in using these other sources. First, no embryos are destroyed in deriving these cells. For anyone who sets a high standard of protection for the human embryo, the destruction of the embryo calls into question the morality of any use of embryonic stem cells. Second, the use of stem cells from sources other than an embryo may mean that in time, medical researchers will learn how to derive healing cells from the patient's own body. The advantage here is that these cells, when implanted, will not be rejected by the patient's immune system. Embryonic stem cells, which may have advantages in terms of their developmental plasticity, are decidedly problematic because of the immune response.
One way to eliminate the immune response is to use nuclear transfer to create an embryo for the patient, harvesting stem cells from that embryo (thereby destroying it) and implanting these cells in the patient. Because they bear the patient's DNA, they should not be rejected. This approach is medically complicated, however, and involves the morally problematic step of creating an embryo to be destroyed for the benefit of another.
As a result of the developments in the underlying science and technologies, biotechnology is able to modify any form of life in ways that seem to be limited only by the imagination or the market. Biotechnology has produced genetically modified microorganisms for purposes ranging from toxic waste clean-up to the production of medicine. For example, by inserting a human gene into a bacterium that is grown in bulk, biotechnology is able to create a living factory of organisms that have been engineered to make a specific human protein. Such technologies may also be used to enhance the virulence of organisms, to create weapons for bioterrorism, or to look for means of defense against such weapons. Aside from obvious concerns about weapons development, religious institutions and scholars have not objected to these uses of biotechnology, although some Protestant groups question the need for patents, especially when sought for specific genes.
Plants, perhaps the first organisms modified by the earliest biotechnology, remain the subject of intense efforts. Around the year 2000, major advances were made in plant genome research, leading to the possibility that the full gene system of some plant species can be studied in detail, and the ways in which plants respond to their environment may be understood as never before. Some attention is given to plants for pharmaceutical purposes, but the primary interest of biotechnology in plants is to improve their value and efficiency as sources of food. For instance, attempts have been made to increase the protein value of plants like rice. The dependence of farm plants on fertilizer and pesticides may also be reduced using biotechnology to engineer plants that, for instance, are resistant to certain insects.
In the 1990s, the expanding use of genetically modified plants in agriculture was met with growing concerns about their effects on health and on the environment. Adding proteins to plants by altering their genes might cause health problems for at least some who consume the plants, perhaps through rare allergic reactions. Genes that produce proteins harmful to some insects may cause harm to other organisms, and they might even jump from the modified farm plant to wild plants growing nearby. Furthermore, some believe that consumers have a right to avoid food that is altered by modern biotechnology, and so strict segregation and labeling must be required. Deeply held values about food and, to some extent, its religious significance underlie many of these concerns. In Europe and the United Kingdom, where public opposition to genetically modified food has been strong, some churches have objected to excessive reliance upon biotechnology in food production and have supported the right of consumers to choose, while at the same time recognizing that biotechnology can increase the amount and the value of food available to the world's neediest people.
Animals are also modified by biotechnology, and this raises additional concerns for animal welfare. Usually the purpose of the modification is related to human health. Biotechnologists may, for example, create animals that produce pharmaceuticals that are expressed, for instance, in milk, or they may create animal research models that mimic human disease. These modifications usually involve a change in the animal germline—that is, they are transmissible to future generations and they affect every cell in the body. Such animals may be patented, at least in some countries. All this raises concern about what some see as the commodification of life, the creation of unnecessary suffering for the animals, and a reductionistic attitude toward nature that sees animals as nothing but raw materials that may be reshaped according to human interest.
It is the human applications of biotechnology, however, that elicit the most thorough and intense religious responses. As of 2002, genetic technologies are used to screen for a wide range of genetic conditions, but treatments for these diseases are slow to develop. Screening and testing of pregnancies, newborns, and adults have become widespread in medicine, and the resulting knowledge is used to plan for and sometimes prevent the development of disease, or to terminate a pregnancy in order to prevent the birth of an infant with foreseeable health problems. Some religious bodies, especially Roman Catholic and Orthodox Christian, vigorously criticize this use of genetic testing. One particular use of prenatal testing—to identify the sex of the unborn and to abort females—is thought to be widespread in cultures that put a high priority on having sons, even though it is universally criticized. It is believed that the uses of testing will grow, while the technologies to treat disease will lag behind.
Attempts at treatment lie along two general pathways: pharmaceuticals and gene therapy. Biotechnology offers new insight into the fundamental processes of disease, either by the creation of animal models or by insight into the functions of human cells. With this understanding, researchers are able to design pharmaceutical products with precise knowledge of their molecular and cellular effects, with greater awareness of which patients will benefit, and with fewer side effects. This is leading to a revolution in pharmaceutical products and is proving to be effective in treating a range of diseases, including cancer, but at rapidly increasing costs and amidst growing concerns about access to these benefits, especially in the poorest nations.
Gene therapy, begun in human beings in 1990, tries to treat disease by modifying the genes that affect its development. Originally the idea was to treat the classic genetic diseases, such as Tay Sachs or cystic fibrosis, and it is expected that in time this technique will offer some help in treating these diseases. But gene therapy will probably find far wider use in treating other diseases not usually seen as genetic because researchers have learned how genes play a role in the body's response to every disease. Modifying this response may be a pathway to novel therapies, by which the body treats itself from the molecular level. For instance, it has been shown that modified genes can trigger the regeneration of blood vessels around the heart. In time these approaches will probably be joined with stem cell techniques and with other cell technologies, giving medicine a range of new methods for modifying the body in order to regenerate cells and tissues.
Religious opinion has generally supported gene therapy, seeing it as essentially an extension of traditional therapies. At the same time, both religious scholars and bioethicists have begun to debate the prospect that these technologies will be used not just to treat disease but to modify traits, such as athletic or mental ability, that have nothing to do with disease, perhaps to enhance these traits for competitive reasons. Many accept the idea of therapy but reject enhancement, believing that there is a significant difference between the two goals. Many scholars, however, are skeptical about whether an unambiguous distinction can be drawn, much less enforced, between therapy and enhancement. Starting down the pathway of gene therapy may mean that human genetic enhancement is likely to follow. This prospect raises religious concerns that people who can afford to do so will acquire genetic advantages that will lead to further privilege, or that people will use these technologies to accommodate rather than challenge social prejudices.
It is also expected that these techniques will be joined with reproductive technologies, opening the prospect that future generations of humans can be modified. The prospect of such germline modification is greeted with fear and opposition by many, usually for reasons that suggest religious themes. In Europe, germline modification is generally rejected as a violation of the human rights of future generations, specifically the right to be born with a genome unaffected by technology. In the United States, the opposition is less adamant but deeply apprehensive about issues of safety and about the long-term societal impact of what are popularly called "designer babies." Religious bodies have supported these concerns and have called either for total opposition or careful deliberation.
How far biotechnology can go is limited by the complexities of life processes, in particular in the subtleties of interaction between DNA and the environment. Biotechnology itself helps researchers discover these subtleties, and as much as biotechnology depends upon the sciences of biology and genetics, it must be noted that the influence between technology and science is reciprocal. The Human Genome Project, for instance, opened important new questions about human evolution and about how DNA results in proteins. Knowledge of the genomes of various species reveals that the relationship between human beings and distant species, such as single-celled or relatively simple organisms, turns out to be surprisingly close, suggesting that evolution conserves genes as species diverge.
Perhaps even more surprising is the way in which the Project has challenged the standard view in modern genetics of the tight relationship between each gene and its protein, the so-called dogma of one gene, one protein. It turns out that human beings have about one hundred thousand proteins but only about thirty-three thousand genes, and that genes are more elusive and dynamic than once thought. It appears that DNA sequences from various chromosomes assemble to become the functional gene, the complete template necessary to specify the protein, and that these various sequences can assemble in more than one way, leading to more than one protein. Such dynamic complexity allows some thirty-three thousand DNA coding sequences to function as the templates for one hundred thousand proteins. But this complexity, in view of the limited understanding of the processes that define it, means that the ability to modify DNA sequences may have limited success and unpredictable consequences, which should lower confidence in genetic engineering, especially when applied to human beings.
Biotechnology is further limited by financial factors. Most biotechnology is pursued within a commercial context, and the prospect of near-term financial return must be present to support research. Biotechnology depends upon access to capital and upon legal protection for intellectual property, such as the controversial policy of granting patent protection on DNA sequences or genes and on genetically modified organisms, including mammals. This financial dependence is itself a matter of controversy, giving rise to the fear that life itself is becoming a mere commodity or that the only values are those of the market.
A look ahead
There is no reason, however, to think that biotechnology has reached the limits of its powers. On the contrary, biotechnology is growing not just in the scope of its applications but in the range and power of its techniques. Biotechnology's access to the whole genomes of human beings and other species means that the dynamic action and interaction of the entire set of genes can be monitored. In one sense, the completion of full genomes ushers in what some have called post-genomic biotechnology, characterized by a new vantage point of a systematic overview of the cell and the organism. This is proving valuable, for instance, in opening new understandings of cancer as a series of mutation events within a set of cells in the body. Attention is turning, however, from the study of genes to the study of proteins, which are more numerous than genes but also more dynamic, coming quickly into and out of existence in the trillions of cells of the human body according to precise temporal and spatial signals. Most human proteins are created only in a small percentage of cells, during a limited period of human development, and only in precisely regulated quantities. Studying this full set of proteins, in all its functional dynamism, is a daunting task requiring technologies that do not exist at the beginning of the twenty-first century. The systematic study of proteins, called proteomics, may in fact become a new international project for biology, leading in time to a profound expansion of the powers of biotechnology.
In time, researchers will develop powerful new methods for modifying DNA, probably with far higher precision and effectiveness than current techniques allow, and perhaps with the ability to transfer large amounts of DNA into living cells and organisms. Computer power, which is essential to undertakings like the Human Genome Project and to their application, continues to grow, along with developments such as the so-called gene chip, using DNA as an integrated part of the computing device. Advances in engineering at the very small scale, known as nanotechnology (from nanometer, a billionth of a meter), suggest that molecular scale devices may someday be used to modify biological functions at the molecular level. For instance, nanotechnology devices in quantity may be inserted into the human body to enter cells, where they might modify DNA or other molecules. In another area of research, scientists are exploring the possibility that DNA itself may be used as a computer or a data storage device. DNA is capable of storing information more efficiently than current storage media, and it may be possible to exploit this capacity.
It is impossible to predict when new techniques will be developed or what powers they will bring. It is clear, however, that new techniques will be found and that they will converge in their effectiveness to modify life. Precisely designed pharmaceutical products will be available to treat nearly every disease, often by interrupting them at the molecular level and doing so in ways that match the specific needs of the patient. Stem cells, whether derived from embryos or from patients themselves, will probably be used to regenerate nearly any tissue or cell in the body, perhaps even portions of organs, including the brain. The genes in patients' bodies will be modified, either to correct a genetic anomaly that underlies a disease or to trigger a special response in specific cells to treat a disease or injury. It is more difficult to foresee the full extent of the long-term consequences of biotechnology on nonhuman species, on the ecosystem, on colonies of life beyond Earth, and on the human species itself; estimates vary in the extreme. Some suggest that through these means, human beings will engineer their own biological enhancements, perhaps becoming two or more species.
The prospect of these transformations has evoked various religious responses, and scholars from many traditions have been divided in their assessments. Those who support and endorse biotechnology stress religious duties to heal the sick and feed the hungry. Most hold the view that nature is to be improved, perhaps within limits, and that human beings are authorized to modify the processes of life. Some suggest that creation is not static but progressive, and that human beings are co-creators with God in the achievement of its full promise.
Others believe biotechnology will pervert nature and undermine human existence and its moral basis. They argue, for instance, that genetic modifications of offspring will damage the relationship between parents and children by reducing children to objects, products of technology, and limit their freedom to grow into persons in relationship with others. Some warn that saying yes to biotechnology now will make it impossible to say no in the future. Still others suggest that the point is not to try to stop biotechnology but to learn to live humanely with its powers, and as much as possible to steer it away from selfish or excessive uses and toward compassionate and just ends.
See also Cloning; Darwin, Charles; DNA; Evolution; Eugenics; Gene Patenting; Gene Therapy; Genetically Modified Organisms; Genetic Engineering; Genetics; Genetic Testing; Human Genome Project; In Vitro Fertilization; Reproductive Technology; Stem Cell Research
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BIOTECHNOLOGY. Biotechnology, in its broadest sense, is the use of biological systems to carry out technical processes. Food biotechnology uses genetic methods to enhance food properties and to improve production, and in particular uses direct (rather than random) strategies to modify genes that are responsible for traits such as a vegetable's nutritional content. Using modern biotechnology, scientists can move genes for valuable traits from one plant into another plant. This way, they can make a plant taste or look better, be more nutritious, protect itself from insects, produce more food, or survive and prosper in inhospitable environments, for example, by incorporating tolerance to increased soil salinity. Simply put, food biotechnology is the practice of directing genetic changes in organisms that produce food in order to make a better product.
In nature, plants produce their own chemical defenses to ward off disease and insects thereby reducing the need for insecticide sprays. Biotechnology is often used to enhance these defenses. Some improvements are crop specific. For example, potatoes with a higher starch content will absorb less oil when frying, and tomatoes with delayed ripening qualities will have improved taste and freshness.
Paving the Way to Modern Biotechnology
Advances in science over many years account for what we know and are able to accomplish with modern biotechnology and food production. A brief review of genetics and biochemistry is useful in evaluating the role of biotechnology in our food supply.
Proteins are composed of various combinations of amino acids. They are essential for life—both for an organism's structure, and for the metabolic reactions necessary for the organism to function. The number, kind, and order of amino acids in a specific protein determine its properties. Deoxyribonucleic acid (DNA), which is present in all the cells of all organisms, contains the information needed for cells to put amino acids in the correct order. In other words, DNA contains the genetic blueprint determining how cells in all living organisms store, duplicate, and pass information about protein structure from generation to generation.
In 1953 James Watson and Francis Crick published their discovery that the molecular structure of DNA is a double helix, for which they, along with Maurice H. F. Wilkins, won a Nobel Prize in 1962. Two strands of DNA are composed of pairs of chemicals—adenine (A) and thymine (T); and guanine (G) and cytosine (C). A segment of DNA that encodes enough information to make one protein is called a gene. It is the order of DNA's base pairs that determines specific genes that code for specific proteins, which determines individual traits.
By 1973 scientists had found ways to isolate individual genes, and by the 1980s, scientists could transfer single genes from one organism to another. This process, much like traditional crossbreeding, allows transferred traits to pass to future generations of the recipient organism.
One Goal, Two Approaches
The objective of plant biotechnology and traditional crop breeding is the same: to improve the characteristics of seed so that the resulting plants have new, desirable traits. The primary difference between the two techniques is how the objective is achieved. Plant breeders have used traditional tools such as hybridization and crossbreeding to improve the quality and yield of their crops with a resulting wide variability in our foods. These traditional techniques resulted in several benefits, such as greatly increased crop production and improved quality of food and feed crops, which has proven beneficial to growers and producers as well as consumers through a reduction of the cost of food for consumers. However, traditional plant breeding techniques do have some limits; only plants from the same or similar species can be interbred. Because of this, the sources for potential desirable traits are finite. In addition, the process of crossbreeding is very time-consuming, at times taking ten to twelve years to achieve the desired goal—and complications can arise because all genes of the two "parent" plants are combined together. This means that both the desirable and undesirable traits may be expressed in the new plant. It takes a significant amount of time to remove the unwanted traits by "back crossing" the new plant over many generations to achieve the desired traits. These biotech methods can preserve the unique genetic composition of some crops while allowing the addition or incorporation of specific genetic traits, such as resistance to disease. However, development of transgenic crop varieties still requires a significant investment of time and resources.
The Many Applications of Biotechnology
Since the earliest times, people have been using simple forms of biotechnology to improve their food supply, long before the discovery of the structure of DNA by Watson and Crick. For example, grapes and grains were modified through fermentation with microorganisms and used to make wine, beer, and leavened bread. Modern biotechnology, which uses the latest molecular biology technology, allows us to more directly modify our foods. Whereas traditional plant breeding mixes tens of thousands of genes, biotechnology allows for the transfer of a single gene, or a few select genes or traits. The most common uses thus far have been the introduction of traits that help farmers simplify crop production, reduce pesticide use in some crops, and increase profitability by reduction of crop losses to weeds, insect damage, or disease.
In general, the early applications of crop biotechnology have been at points in our food supply chain where economic benefit can be gained. The following are examples of modern biotechnology where success has been achieved or is in progress.
Insect resistance. Crop losses from insect pests can cause devastating financial loss for growers and starvation in developing countries. In the United States and Europe, thousands of tons of pesticides are used to control insects. Using modern biotechnology, scientists and farmers have removed the need for the use of some of these chemicals. Insect-protected plants are developed by introducing a gene into a plant that produces a specific protein from a naturally occurring soil organism. Bacillus thuringiensis (Bt) is one of many bacteria naturally present in soil. This bacterium is known to be lethal to certain classes of insects, and only those organisms. The Bt protein produced by the bacterium is the natural insecticide. Growing foods, such as Bt corn, can help eliminate the application of chemical pesticides and reduce the cost of bringing a crop to market. The introduction of insect-protected crops such as Bt cotton has allowed reduced use of chemical pesticides. This suggests that genetically engineered food crops can also be grown with reduced use of pesticides, a development that would be welcomed by the general public.
Herbicide tolerance. Every year, farmers must battle weeds that compete with their crops for water, nutrients, sunlight, and space. Weeds can also harbor insects and disease. Farmers routinely use two or more different chemicals on a crop to remove both grass and broadleaf weeds. In recent years new "broad-spectrum" chemicals have been discovered that control all these weeds and therefore require only one application of one chemical to the crop. To provide crops with a defense against these nonselective herbicides, genes have been added to plants that render the chemicals inactive—but only in the new, herbicide-resistant crop. Many benefits come from these crops, including better and more flexible weed control for farmers, increased use of conservation tillage (involving less working of the soil and thereby decreasing erosion), and promoting the use of herbicides that have a better environmental profile (that is, that are less toxic to nontarget organisms).
Disease resistance. Many viruses, fungi, and bacteria can cause plant diseases, resulting in crop damage and loss. Researchers have had great success in developing crops that are protected from certain types of plant viruses by introducing DNA from the virus into the plant. In essence, the plants are "vaccinated" against specific diseases. Because most plant viruses are spread by insects, farmers can use fewer insecticides and still have healthy crops and high yields.
Drought tolerance and salinity tolerance. As the world population grows and industrial demand for water supplies increases, the amount of water used to irrigate crops will become more expensive or unavailable. Creating plants that can withstand long periods of drought or high salt content in soil and groundwater will help overcome these limitations. Although genetically engineered crops with enhanced drought tolerance are not yet commercially available, significant research advances are pointing the way to creating these in the future.
Food applications. Research into applications of biotechnology to food production covers a broad range of possibilities. Examples of food applications also include increasing the nutrient content of foods where deficiencies are widespread in the population. For example, researchers have successfully increased the amount of iron and beta-carotene (the precursor to vitamin A in humans) in carrots and "golden rice"—a biotech rice developed by the Rockefeller Foundation that may help provide children in developing nations with the vitamin A they need to reduce the risk of vision problems or blindness.
Another example of food biotechnology is crops modified for higher monounsaturated fatty acid levels in the vegetable to make them more "heart-healthy." Efforts are also under way to slow the ripening of some crops, such as bananas, tomatoes, peppers, and tropical fruits, to allow time to ship them from farms to large cities while preserving taste and freshness.
Other possible food applications for which pioneering research is under way include grains and nuts where naturally occurring allergens have been reduced or eliminated. Potatoes with higher starch content also promise to have the added potential to reduce the fat content in fried potato products, such as french fries and potato chips. This is because the starch replaces water in the potatoes, causing less fat to be absorbed into the potato when it is fried.
Edible vaccines. Vaccines that are commonly used today are often costly to produce and require cold storage conditions when shipped from their point of manufacture in the developed world to points of use in the developing world. Research has shown that protein-based vaccines can be designed into edible plants so that simple eating of the material leads to oral immunization. This technology will allow local production of vaccines in developing countries, reduction of vaccine costs, and promotion of global immunization programs to prevent infectious diseases.
Global food needs. The world population has topped six billion people and is predicted to double by 2050. Ensuring an adequate food supply for this booming population is going to be a major challenge in the years to come. Biotechnology can play a critical role in helping to meet the growing need for high-quality food produced in more sustainable ways.
What Are Consumers Saying?
Crops modified by biotechnology (also known as genetically modified or GM crops) have been the subjects of public discussion in recent years. Considerable public discussion may be attributed to the public's interest in the safety and usefulness of new products. Although biotechnology has a strongly supported safety record, some groups and organizations abroad and in the United States have expressed a desire for stronger regulation of biotechnology-derived products than of similar foods derived from older technology. The assessment of the need for new regulation is related to an understanding of the science itself, as was detailed in the sections above; this is a continual process of development.
Consumer acceptance is critical to the success of biotechnology around the world. Attitudes toward biotechnology vary from country to country because of cultural and political differences, in addition to many other influences.
In the United States, the majority of consumers are supportive about the potential benefits biotechnology can bring. Generally, U.S. consumers feel they would like to learn more about the topic, and respond favorably when they are given accurate, science-based information on the subject of food biotechnology.
See also Agriculture since the Industrial Revolution; Agronomy; Crop Improvement; Ecology and Food; Environment; Food Politics: United States; Food Safety; Gene Expression, Nutrient Regulation of; Genetic Engineering; Genetics; Government Agencies; Green Revolution; High-Technology Farming; Inspection; Marketing of Food; Toxins, Unnatural, and Food Safety.
Arntzen, Charles J. "Agricultural Biotechnology." In Nutrition and Agriculture. United Nations Administrative Committee on Coordination, Subcommittee on Nutrition, World Health Organization. September 2000
Borlaug, Norman E. "Feeding a World of 10 Billion People: The Miracle Ahead." Lecture given at De Moutfort University, Leicester, England, May 1997. http://agriculture.tusk.edu/biotech/monfort2html International Food Information Council (IFIC). "Food Biotechnology Overview." Washington, D.C.: February 1998. Available at http://ific.org.
Cho, Mildred, David Magnus, Art Caplan, and Daniel McGee. "Ethical Considerations in Synthesizing a Minimal Genome." Science 286 (10 December 1999): 2087–2090.
Charles J. Arntzen Susan Pitman Katherine Thrasher
Three government agencies monitor the development and testing of biotechnology crops: the Food and Drug Administration (FDA), the U.S. Department of Agriculture (USDA), and the Environmental Protection Agency (EPA). These agencies work together to ensure that biotechnology foods are safe to eat, safe to grow, and safe for the environment.
U.S. Food and Drug Administration (FDA): Lead agency in assessing safety for human consumption of plants or foods that have been altered using biotechnology, including foods that have improved nutritional profiles, food quality, or food processing advantages.
U.S. Department of Agriculture: Provides regulatory oversight to ensure that new plant varieties pose no harm to production agriculture or to the environment. USDA's Animal and Plant Health Inspection Service (APHIS) governs the field testing of biotechnology crops to determine how transgenic varieties perform relative to conventional varieties, and the balance between risk and reward.
Environmental Protection Agency (EPA): EPA provides regulatory and safety oversight for new plant varieties, such as insect-protected biotechnology crops. EPA regulates any pesticide that may be present in food to provide a high margin of safety for consumers.
Genetically Modified Organisms: Health and Environmental Concerns
There is really little doubt that, at least in principle, the development of genetically modified organisms (GMOs) can offer many advantages. Genetically modified organisms have included crops that are largely of benefit to farmers and not clearly of broad public value. Plans for development of GMOs include foods that have far greater nutritional and even pharmaceutical benefit; crops that can grow in regions that currently cannot provide enough food for subsistence; and foods that are more desirable in terms of traits that the public wants. The market forces that largely determine which products are developed are complicated, and there are important trade-offs: the traits that may be needed to feed a starving world are different from the traits farmers in the United States want, and both may differ from the characteristics the paying public supports.
Most criticisms of genetic engineering focus on food safety and environmental impacts. What impact will GMOs have on the health of those who eat them? Will some individuals develop allergic reactions? The new technology makes it possible to cross species barriers with impunity. A scare over StarLink corn is instructive of this kind of problem. "Bt corn," a common GMO, includes a gene from Bacillus thuringienis, which produces a pesticide that kills the European corn borer. StarLink is a variety of Bt corn that includes a protein (Cry9C) that does not break down as easily in the body, which increases the risk of allergic reactions in some people (though there are no verified cases of this). StarLink corn was approved for animal feed but not for human consumption. Unfortunately it is difficult if not impossible to keep the food supply for animals and humans separate. The result has been the discovery of small amounts of StarLink corn throughout the food supply. (Of course, there is also the question whether a small trace of Cry9C in a fast-food taco is the greatest health problem involved in such a meal.)
A second set of concerns arises over the environmental impact of GMOs. There are several different concerns. First, there are worries about gene flow. The same genes that may one day make it possible for plants to grow in poor, salty soil or in relatively arid regions could create an ecological nightmare by allowing these crops to spread beyond their normal range as a result of the gene(s) that have been transferred into the crop itself, or if those same genes should be introduced to other plants. This can happen through outcrossing between the GMOs and closely related plants. For example, GM wheat could cross with native grasses in South America to alter the makeup of the ecosystem and potentially create "super weeds," a possibility that has raised concerns in the "Wheat Belt" of the United States and elsewhere. Even in the absence of gene flow, the GMOs themselves could become super weeds (or the animal equivalent) as a result of the traits that make them better suited to new habitats. The environmental trade-off for technology that makes it possible to produce sustainable agriculture or aquaculture in regions where it cannot "naturally" flourish is the significant risk of loss of biodiversity and the unchecked spread of plants or animals into unintended regions. (The argument is made, however, that biotechnology can be used to increase yields on the land that is currently used for agricultural production, allowing nonfarm land to be retained as forests and reserves and thereby conserve biodiversity.)
In addition to these concerns over the ecosystem and the creation of superweeds, there is a worry over the potential impact of some GMOs on nontarget organisms. Cornell University researchers found that pollen from Bt corn could kill the larvae of monarch butterflies that ingested it. This raised the fear that these engineered crops could kill butterflies and other nontarget organisms in addition to the corn borer. The consensus from subsequent field research is that Bt corn does not pose a major threat to monarch butterfly populations—loss of habitat in Mexico, where the butterflies overwinter, is a more serious threat. Nevertheless, the Bt corn–butterfly issue showed that it is not always possible to predict the consequences that may arise from the introduction of these crops.
Genetically engineered microorganisms present even greater environmental and health concerns. It will soon be possible to engineer bacteria and viruses to produce deadly pathogens. This could well open a new era in biological weapons in addition to the environmental problems that could result from the release of organisms into the environment. The environmental assessment of the widespread introduction of engineered microorganisms has only barely begun to receive attention (Cho et al., 1999).
These concerns are exacerbated by some inadequacies in the regulatory framework for GMOs. There is a growing sense that the Food and Drug Administration, the U.S. Department of Agriculture, and the Environmental Protection Agency are not sufficiently rigorous or consistent in how they regulate GMOs and that there should be a single set of standards, including a mandatory environmental assessment. The opposition to GMOs in Europe is much more widespread than in the United States, and the single most important factor for the differences between European and American attitudes is the level of confidence in the regulatory institutions that protect the food supply. After "mad cow disease," Europeans do not trust their governments to provide safe food. A similar loss in confidence among U.S. consumers could have a similar effect. In spite of these concerns, however, there have so far been no documented food safety problems resulting from the introduction of GM crops in the mid-1990s and their large-scale consumption by the American public. There have also been no ecological disasters, although the time since their introduction has been too brief for the absence of disaster to be very meaningful. In some crops, notably in Bt cotton, there have been significant reductions in the use of pesticides.
David Magnus with contributions by Peter Goldsbrough
Few developments in science have had the potential for such profound impact on research, technology, and society in general as has biotechnology. Yet authorities do not agree on a single definition of this term. Sometimes, writers have limited the term to techniques used to modify living organisms and, in some instances, the creation of entirely new kinds of organisms.
In most cases, however, a broader, more general definition is used. The Industrial Biotechnology Association, for example, uses the term to refer to any "development of products by a biological process." These products may indeed be organisms or they may be cells, components of cells, or individual and specific chemicals . A somewhat more detailed definition is that of the European Federation of Biotechnology, which defines biotechnology as the "integrated use of biochemistry, microbiology, and engineering sciences in order to achieve technological (industrial) application of the capabilities of microorganisms , cultured tissue cells, and parts thereof."
By almost any definition, biotechnology has been used by humans for thousands of years, long before modern science existed. Some of the oldest manufacturing processes known to humankind make use of biotechnology. Beer, wine, and breadmaking, for example, all occur because of the process of fermentation. During fermentation, microorganisms such as yeasts, molds, and bacteria are mixed with natural products which they use as food. In the case of wine-making, for example, yeasts live on the sugars found in some type of fruit juice, most commonly, grape juice. They digest those sugars and produce two new products, alcohol and carbon dioxide .
The alcoholic beverages produced by this process have been, for better or worse, a mainstay of human civilization for untold centuries. In breadmaking, the products of fermentation are responsible for the wonderful odor (the alcohol) and texture (the carbon dioxide) of freshly-baked bread. Cheese and yogurt are two other products formed when microorganisms act on a natural product, in this case milk—changing its color, odor, texture, and taste.
Biotechnology has long been used in a variety of industrial processes also. As early as the seventeenth century, bacteria were used to remove copper from its ores. Around 1910, scientists found that bacteria could be used to decompose organic matter in sewage, thus providing a mechanism for dealing efficiently with such materials in solid waste . A few years later, a way was found to use microorganisms to produce glycerol synthetically. That technique soon became very important commercially, since glycerol is used in the manufacture of explosives and World War I was about to begin.
Not all forms of biotechnology depend on microorganisms. Hybridization is an example. Farmers long ago learned that they could control the types of animals bred by carefully selecting the parents. In some cases, they actually created entirely new animal forms that do not occur in nature . The mule, a hybrid of horse and donkey, is such an animal.
Hybridization has also been used in plant growing for centuries. Farmers found that they could produce food plants with any number of special qualities by carefully selecting the seeds they plant and by controlling growing conditions. As a result of this kind of process, the 2–3-in (5.1–7.6-cm) vegetable known as maize has evolved over the years into the 12-in (30-cm), robust product called corn. Indeed, there is hardly a fruit or vegetable in our diet today that has not been altered by long decades of hybridization.
Until the late nineteenth century, hybridization was largely a trial-and-error process. Then the work of Gregor Mendel started to become known. Mendel's research on the transmission of hereditary characteristics soon gave agriculturists a solid factual basis on which to conduct future experiments in cross-breeding.
Modern principles of hybridization have made possible a greatly expanded use of biotechnology in agriculture and many other areas. One of the greatest successes of the science has been in the development of new food crops that can be grown in a variety of less-than-optimal conditions. The dramatic increase in harvests made possible by these developments has become known as the agricultural revolution or green revolution.
Three decades after the green revolution first changed agriculture in many parts of the world, a number of problems with its techniques have become apparent. The agricultural revolution forced a worldwide shift from subsistence farming to cash farming, and many small farmers in developing countries lack the resources to negotiate this shift. A farmer must make significant financial investments in seed, agricultural chemicals (fertilizers and pesticides), and machinery to make use of new farming techniques. In developing countries, peasants do not have and cannot borrow the necessary capital. The seed, chemicals, machinery, and oil to operate the equipment must commonly be imported, adding to already crippling foreign debts. In addition, the new techniques often have harmful effects on the environment . In spite of problems such as these, however, the green revolution has clearly made an important contribution to the lessening of world hunger.
Modern methods of hybridization have application in many fields besides agriculture. For example, scientists are now using controlled breeding techniques and other methods from biotechnology to insure the survival of species that are threatened or endangered.
The nature of biotechnology has undergone a dramatic change in the last half century. That change has come about with the discovery of the role of deoxyribosenucleic acid DNA in living organisms. DNA is a complex molecule that occurs in many different forms. The many forms that DNA can take allow it to store a large amount of information. That information provides cells with the direction they need to carry out all the functions they have to perform in a living organism. It also provides a mechanism by which that information is transmitted efficiently from one generation to the next.
As scientists learned more about the structure of the DNA molecule, they discovered precisely and in chemical terms how genetic information is stored and transmitted. With that knowledge, they have also developed the ability to modify DNA, creating new instructions that direct cells to perform new and unusual functions. The process of DNA modification has come to be known as genetic engineering . Since genetic engineering normally involves combining two different DNA molecules, it is also referred to as recombinant DNA research.
There is little doubt that genetic engineering is the best known form of biotechnology today. Indeed, it is easy to confuse the two terms and to speak of one when it is the other that is meant. However, the two terms are different in the respect that genetic engineering is only one type of biotechnology.
In theory, the steps involved in genetic engineering are relatively simple. First, scientists decide what kind of changes they want to make in a specific DNA molecule. They might, in some cases, want to alter a human DNA molecule to correct some error that results in a disease such as diabetes. In other cases, a researcher might want to add instructions to a DNA molecule that it does not normally carry. He or she might, for example, want to include instructions for the manufacture of a chemical such as insulin in the DNA of bacteria that normally lack the ability to make insulin.
Second, scientists find a way to modify existing DNA to correct errors or add new information. Such methods are now well developed. In one approach, enzymes that "recognize" certain specific parts of a DNA molecule are used to cut open the molecule and then insert the new portion.
Third, scientists look for a way to insert the "correct" DNA molecule into the organisms in which it is to function. Once inside the organism, the new DNA molecule may give correct instructions to cells in humans (to avoid genetic disorders), in bacteria (resulting in the production of new chemicals), or in other types of cells for other purposes.
Accomplishing these steps in practice is not always easy. One major problem is to get an altered DNA molecule to express itself in the new host cells. That the molecule is able to enter a cell does not mean that it will begin to operate and function (express itself) as scientists hope and plan. This means that many of the expectations held for genetic engineering may not be realized for many years.
In spite of problems, genetic engineering has already resulted in a number of impressive accomplishments. Dozens of products that were once available only from natural sources and in limited amounts are now manufactured in abundance by genetically engineered microorganisms at relatively low cost. Insulin, human growth hormone, tissue plasminogen activator, and alpha interferon are examples. In addition, the first trials with the alteration of human DNA to cure a genetic disorder were begun in 1991.
The prospects offered by genetic engineering have not been greeted with unanimous enthusiasm by everyone. Many people believe that the hope of curing or avoiding genetic disorders is a positive advance. But they question the wisdom of making genetic changes that are not related to life-threatening disorders. Should such procedures be used for helping short children become taller or for making new kinds of tomatoes? Indeed, there are some critics who oppose all forms of genetic engineering, arguing that humans never have the moral right to "play God" with any organism for any reason. As the technology available for genetic engineering continues to improve, debates over the use of these techniques in practical settings are almost certainly going to continue—and to escalate—in the future.
As progress in genetic engineering goes forward, so do other forms of biotechnology. The discovery of monoclonal antibodies is an example. Monoclonal antibodies are cells formed by the combination of tumor cells with animal cells that make one and only one kind of antibody. When these two kinds of cells are fused, they result in a cell that reproduces almost infinitely and that recognizes one and only one kind of antigen. Such cells are extremely valuable in a vast array of medical, biological, and industrial applications, including the diagnosis and treatment of disease, the separation and purification of proteins, and the monitoring of pregnancy.
Biotechnology became a point of contention in 1992 during planning for the United Nations Earth Summit in Rio de Janeiro. In draft versions of the treaty on biodiversity , developing nations insisted on provisions that would force biotechnology companies in the developed world to pay fees to developing nations for the use of their genetic resources (the plants and animals growing within their boundaries). Currently, companies have free access to most of these raw materials used in the manufacture of new drugs and crop varieties. President George Bush argued that this provision would place an unfair burden on biotechnology companies in the United States, and he refused to sign the biodiversity treaty that contained this clause. For now, it seems that, for a second time, profits to be reaped from biotechnological advances will elude developing countries. (The Clinton administration subsequently endorsed the provisions of the biodiversity treaty and it was signed by Madeleine Albright, U. S. ambassador to the United Nations, on June 4, 1993.)
[David E. Newton ]
Fox, M. W. Superpigs and Wondercorn: The Brave New World of Biotechnology and Where It May All Lead. New York: Lyons and Buford, 1992.
Mellon, M. Biotechnology and the Environment. Washington, D.C.: National Biotechnology Policy Center of the National Wildlife Federation, 1988.
Kessler, D. A., et al. "The Safety of Foods Developed by Biotechnology." Science (26 June 1992): 1747-1749+.
Biotechnology is the use of any technique involving living organisms to manufacture or change products, to improve the desired characteristics of a plant or animal, or to alter microorganisms for a purpose.
The word biotechnology was coined in 1919 by Karl Ereky to apply to the interaction of biology with human technology. Today, biotechnology refers to a broad range of technologies from genetic engineering (recombinant DNA techniques) to animal breeding and industrial fermentation. More precisely, biotechnology is defined as the integrated use of biochemistry, microbiology, and engineering sciences in order to achieve technological (industrial) application of the capabilities of microorganisms, cultured tissue cells, and their components.
Biotechnology has a long history. For example, yeast microorganisms were harnessed to prepare wine by Egyptians some 4, 000 years before the birth of Christ. In 1865, Gregor Mendel (1822–1884) presented his laws of heredity, which he deduced by the careful observation of the results of breeding different types of pea plants. Although he did not realize it at the time, Mendel was observing the results of the exchange and altered expression of genetic material.
Biotechnology has undergone a dramatic change since the 1970s. Modern biotechnology is largely based on recent developments in molecular biology, especially those in genetic engineering. Organisms from bacteria to cows are being genetically modified to produce products that include pharmaceuticals and foods. New, biotechnology-grounded methods of disease gene isolation, analysis, and detection, as well as gene therapy, are changing medicine.
The modern day conception of biotechnology, with the deliberate experimental manipulation of genetic material, had its roots in the mid years of the twentieth century. In 1940, deoxyribonucleic acid (DNA) was isolated by Oswald Avery (1877–1955). Thirteen years later, James Watson and Francis Crick (1928– and 1916–2004) described the double helix structure of DNA, a feat that earned them a Nobel Prize just a few years later. The modern age of biotechnology began in 1973, when Stanley Cohen (1922–) and Herbert Boyer (1936–) devised recombinant DNA technology; the deliberate introduction of DNA from one species into another. Their work made possible feats such as the production of human insulin by the bacterium Escherichia coli. This genetically engineered human insulin was, in fact, the first genetically engineered product approved for sale in the United States in 1982.
In theory, the steps involved in genetic engineering are relatively simple. First, scientists decide the changes to be made in a specific DNA molecule. It is desirable in some cases to alter a human DNA molecule to correct errors that result in a disease such as diabetes. In other cases, researchers might add instructions to a DNA molecule that it does not normally carry: instructions for the manufacture of a chemical such as insulin, for example, in the DNA of bacteria that normally lack the ability to make insulin. Scientists also modify existing DNA to correct errors or add new information. Such methods are now well developed. Finally, scientists look for a way to put the recombinant DNA molecule into the organisms in which it is to function. Once inside the organism, the new DNA molecule give correct instructions to cells in humans to correct genetic disorders, in bacteria (resulting in the production of new chemicals), or in other types of cells for other purposes.
Molecular geneticists use molecular cloning techniques to replicate various genetic materials such as gene segments and cells. The process of molecular cloning involves isolating a DNA sequence of interest and obtaining multiple copies of it in an organism that is capable of growth over extended periods. Large quantities of the DNA molecule can then be isolated in pure form for detailed molecular analysis. The now-routine ability to generate virtually endless copies (clones) of a particular sequence is the basis of recombinant DNA technology and its application to human and medical genetics.
A technique called positional cloning is used to map the location of a human disease gene. Positional cloning is a relatively new approach to finding genes. A particular DNA marker is linked to the disease if, in general, family members with certain nucleotides at the marker always have the disease, and family members with other nucleotides at the marker do not have the disease. Once a suspected linkage result is confirmed, researchers can then test other markers known to map close to the one found, in an attempt to move closer and closer to the disease gene of interest. The gene can then be cloned if the DNA sequence has the characteristics of a gene and it can be shown that particular mutations in the gene confer disease.
Differences between the organization of the genetic material of organisms like bacteria and “higher” organisms such as humans, and the difference in how the genetic traits coded for by the material are expressed, has complicated the advances in biotechnology. But, increasingly, such species differences are being understood.
Genetic engineering has resulted in a number of impressive accomplishments. Dozens of products that were once available only from natural sources and in limited amounts are now manufactured in abundance by genetically engineered microorganisms at relatively low cost. Insulin, human growth hormone, tissue plasminogen activator, and alpha interferon are examples. In addition, the first trials with the alteration of human DNA to cure a genetic disorder began in 1991.
Commercial applications of biotechnology are numerous. For example, foods are being genetically altered to engineer in more nutritional compounds. The nutraceutical industry is growing to become a potent economic force, generating billions of dollars in sales each year in the United States alone. Genetic manipulation can also help preserve foods longer, allowing a fresher product to reach the supermarket shelves.
An aspect of biotechnology that has garnered much attention since the 1990s is cloning. Until 1997, a fully developed organism could not be cloned. But, in early 1997, the first success at producing live animals by embryo cloning occurred in Edinburgh, Scotland. The procedure that produced Dolly the sheep was reported in the March 6, 1997 edition of Nature.
While embryo cloning is still a hit or miss procedure, the consensus among researchers involved in embryo cloning is that cloning animal embryos will be perfected. The resulting ease of genetic tailoring could produce higher yielding and disease-resistant livestock.
Cloning embryos is similar to what happens naturally when identical twins are created in the womb. All human embryos begin as a single cell. Normally, millions of rounds of division and the formation
Hybridization— Development of new breeds of plants or animals achieved by combining the desired traits of two or more species in controlled breeding.
Recombinant DNA research— A process of DNA modification by which two different DNA molecules are combined.
of cells that differ in structure and function from other cells gives rise to a human. With identical twins, as the cell divides it separates into two separate, individual cells. The two separate, individual cells then divide and differentiate independently. The result is two embryos that are identical in the composition of their genetic material.
In embryo cloning, a cell is mechanically encouraged to divide into two separate, individual cells. These grow and develop separately, creating identical twins. There is continuing debate around the moral and ethical limits on cloning human embryos. As of 2006, it is illegal to use federal research funds in the United States to clone human embryos. In November of 2001, the human cloning debate was raised from a theoretical discussion to a concrete discussion. Then, a company in suburban Boston announced that a human cell had been cloned to provide stem cells for research. While the experiment was carried on for only a few cell divisions, the technology required to develop a cloned human being may be almost in place. Indeed, early in 2006 the same company announced its success in establishing cloned human cells that were capable of at least a few cell divisions.
The prospects offered by biotechnology have not been greeted with unanimous enthusiasm by everyone. Many scientists and laypersons assert that the hope of curing or avoiding genetic disorders through biotechnology is a positive advance. Some hold that the genetically derived nutritional enhancement of foods, such as the nutritional supplementation of rice grown in developing countries, is a worthy aim. Others oppose all forms of genetic engineering, or warn of the dangers of having such technology as the commercial property of a few large companies. There are also concerns about genetic privacy, the effects of transgenic organisms on other organisms and the environment, and animal rights.
Borem, Aluizio, Fabricio Santos, and David E. Bowen. Understanding Biotechnology. New York: Prentice Hall, 2003.
Friedman, Yali. Building Biotechnology: Starting, Managing, and Understanding Biotechnology Companies. Niagara Falls, NY: Thinkbiotech, 2006.
The term biotechnology refers to the use of scientific techniques, including genetic engineering, to improve or modify plants, animals, and microorganisms . In its most basic forms, biotechnology has been in use for millennia. For example, Middle Easterners who domesticated and bred deer, antelope, and sheep as early as 18,000 b.c.e.; Egyptians who made wine in 4000 b.c.e.; and Louis Pasteur, who developed pasteurization in 1861, all used biotechnology. In recent years, however, food biotechnology has become synonymous with the terms genetically engineered foods and genetically modified organism (GMO).
Traditional biotechnology uses techniques such as crossbreeding , fermentation , and enzymatic treatments to produce desired changes in plants, animals, and foods. Crossbreeding plants or animals involves the selective passage of desirable genes from one generation to another. Microbial fermentation is used in making wine and other alcoholic beverages, yogurt, and many cheeses and breads. Using enzymes as food additives is another traditional form of biotechnology. For example, papain, an enzyme obtained from papaya fruit, is used to tenderize meat and clarify beverages.
The DNA contained in genes determines inherited characteristics. Modifying DNA to remove, add, or alter genetic information is called genetic modification or genetic engineering. In the early 1980s, scientists developed recombinant DNA techniques that allowed them to extract DNA from one species and insert it into another. Refinements in these techniques have allowed identification of specific genes within DNA—and the transfer of that particular gene sequence of DNA into another species. For example, the genes responsible for producing insulin in humans have been isolated and inserted into bacteria . The insulin that is then produced by these bacteria, which is identical to human insulin, is then isolated and given to people who have diabetes . Similarly, the genes that produce chymosin, an enzyme that is involved in cheese manufacturing, have also been inserted into bacteria. Now, instead of having to extract chymosin from the stomachs of cows, it is made by bacteria. This type of application of genetic engineering has not been very controversial. However, applications involving the use of plants have been more controversial.
Among the first commercial applications of genetically engineered foods was a tomato in which the gene that produces the enzyme responsible for softening was turned off. The tomato could then be allowed to ripen on the vine without getting too soft to be packed and shipped. As of 2002, over forty food crops had been modified using recombinant DNA technology, including pesticide-resistant soybeans, virus-resistant squash, frost-resistant strawberries, corn and potatoes containing a natural pesticide, and rice containing beta-carotene. Consumer negativity toward biotechnology is increasing, not only in the United States, but also in the United Kingdom, Japan, Germany, and France, despite increased consumer knowledge of biotechnology. The principle objections to biotechnology and foods produced using genetic modification are: concern about possible harm to human health (such as allergic responses to a "foreign gene"), possible negative impact to the environment, a general unease about the "unnatural" status of biotechnology, and religious concerns about modification.
Biotechnology in Animals
The most controversial applications of biotechnology involve the use of animals and the transfer of genes from animals to plants. The first animal-based application of biotechnology was the approval of the use of bacterially produced bovine somatotropin (bST) in dairy cows. Bovine somatotropin, a naturally occurring hormone , increases milk production. This application has not been commercially successful, however, primarily because of its expense. The cloning of animals is another potential application of biotechnology. Most experts believe that animal applications of biotechnology will occur slowly because of the social and ethical concerns of consumers.
Concerns about Food Production
Some concerns about the use of biotechnology for food production include possible allergic reactions to the transferred protein . For example, if a gene from Brazil nuts that produces an allergen were transferred to soybeans, an individual who is allergic to Brazil nuts might now also be allergic to soybeans. As a result, companies in the United States that develop genetically engineered foods must demonstrate to the U.S. Food and Drug Administration (FDA) that they did not transfer proteins that could result in food allergies . When, in fact, a company attempted to transfer a gene from Brazil nuts to soybeans, the company's tests revealed that they had transferred a gene for an allergen, and work on the project was halted. In 2000 a brand of taco shells was discovered to contain a variety of genetically engineered corn that had been approved by the FDA for use in animal feed, but not for human consumption. Although several antibiotechnology groups used this situation as an example of potential allergenicity stemming from the use of biotechnology, in this case the protein produced by the genetically modified gene was not an allergen. This incident also demonstrated the difficulties in keeping track of a genetically modified food that looks identical to the unmodified food. Other concerns about the use of recombinant DNA technology include potential losses of biodiversity and negative impacts on other aspects of the environment.
Safety and Labeling
In the United States, the FDA has ruled that foods produced though biotechnology require the same approval process as all other food, and that there is no inherent health risk in the use of biotechnology to develop plant food products. Therefore, no label is required simply to identify foods as products of biotechnology. Manufacturers bear the burden of proof for the safety of the food. To assist them with this, the FDA developed a decision-tree approach that allows food processors to anticipate safety concerns and know when to consult the FDA for guidance. The decision tree focuses on toxicants that are characteristic of each species involved; the potential for transferring food allergens from one food source to another; the concentration and bioavailability of nutrients in the food; and the safety and nutritional value of newly introduced proteins.
Biotechnology and Global Health
The World Health Organization estimates that more than 8 million lives could be saved by 2010 by combating infectious diseases and malnutrition through developments in biotechnology. A study conducted by the Joint Centre for Bioethics at the University of Toronto identified biotechnologies with the greatest potential to improve global health, including the following:
- Hand-held devices to test for infectious diseases including HIV and malaria. Researchers in Latin America have already made breakthroughs with such devices in combating dengue fever.
- Genetically engineered vaccines that are cheaper, safer, and more effective in fighting HIV/AIDS, malaria, tuberculosis, cholera, hepatitis, and other ailments. Edible vaccines could be incorporated into potatoes and other foods.
- Drug delivery alternatives to needle injections, such as inhalable or powdered drugs.
- Genetically modified bacteria and plants to clean up contaminated air, water, and soil.
- Vaccines and microbicides to help prevent sexually transmitted diseases in women.
- Computerized tools to mine genetic data for indications of how to prevent and cure diseases.
- Genetically modified foods with greater nutritional value.
Labeling of genetically modified foods has sparked additional debate. Labels are required on food produced through biotechnology to inform consumers of any potential health or safety risk. For example, a label is required if a potential allergen is introduced into a food product. A label is also required if a food is transformed so that its nutrient content no longer resembles the original food. For example, so-called golden rice has been genetically engineered to have a higher concentration of beta-carotene than regular rice, and thus it must be included on the label. In response to consumer demands, regulators in England have instituted mandatory labeling laws for all packaged foods and menus containing genetically modified ingredients. Similar but less restrictive laws have been instituted in Japan. In Canada, the policy on labeling has remained similar to that of the United States.
Some consumer advocates maintain that not requiring a label on all genetically modified foods violates consumers' right to make informed food choices, and many producers of certain foods, such as foods containing soy protein, now include the term "non-GMO" on the label to indicate that the product does not contain genetically modified ingredients.
The application of recombinant DNA technology to foods, commonly called biotechnology, may be viewed as an extension of traditional cross-breeding and fermentation techniques. The technology enables scientists to transfer genetic material from one species to another, and may produce food crops and animals that are different than those obtained using traditional techniques. The FDA has established procedures for approval of food products manufactured using recombinant DNA technology that require food producers to demonstrate the safety of their products. The American Dietetic Association, the American Medical Association, and the World Health Organization have each adopted statements that techniques of biotechnology may have the potential to improve the food supply. These organizations and others acknowledge that long-term health and environmental impacts of the technology are not known, and they encourage continual monitoring of potential impacts.
see also Additives and Preservatives; Food Safety; Genetically Modified Foods.
M. Elizabeth Kunkel Barbara H. D. Luccia
Altman, Arie, ed. (1998). Agricultural Biotechnology. New York: Marcel Dekker.
Johnson-Green, Perry (2002). Introduction to Food Biotechnology. Boca Raton, FL: CRC Press.
Serageldin, Ismail (1999). "Biotechnology and Food Security in the 21st Century." Science 285:387–389.
Biotechnology, broadly defined, refers to the manipulation of biology or a biological product for some human end. Before recorded history, humans grew selected plants for food and medicines. They bred animals for food, for work, and as pets. The ancient Egyptians learned how to maintain selected yeast cultures, which allowed them to bake and brew with predictable results. These are all examples of biotechnology. In more recent times, however, the term "biotechnology" has mainly been applied to specifically industrial processes that involve the use of biological systems. Today many biotechnology companies use processes that make use of genetically engineered microorganisms.
A Revolution in Biology
Following 1953, when Thomas Watson and Francis Crick published their famous paper on the double helix structure of DNA, a series of independent discoveries were made in chemistry, biochemistry, genetics, and microbiology, which together brought about a revolution in biology and led to the first experiments in genetic engineering in 1973. Because of this revolution, scientists learned to modify living microorganisms in a permanent, predictable way. Bacteria have been made to produce medical products, such as hormones, vaccines, and blood factors, that were formerly not available or available only at great expense or in limited amounts. Crop plants have been developed with increased resistance to disease or insect pests, or with greater tolerance to frost or drought. What has made all these things possible is the collection of biochemical and molecular biological techniques for manipulating genes, which are the basic units of biological inheritance. These are the techniques used in genetic engineering or recombinant DNA technology.
The fusion of traditional industrial microbiology and genetic engineering in the late 1970s led to the development of the modern biotechnology industry. Using recombinant DNA technology, this industry has brought a long and steadily growing list of products into the marketplace. Human insulin produced by genetically engineered bacteria was one of the first of these products. It was followed by human growth hormone; an anti-viral protein called interferon; the immune stimulant called interleukin 2; a tissue plasminogen activator for dissolving blood clots; two blood-clotting factors, labeled VIII and IX, which are administered to hemophiliacs; and many other products.
The production of certain chemicals has already become an important biotechnological industry. Vitamin C is a prime example. Humans, as well as other primates, guinea pigs, the Indian fruit bat, several species of fish, and a number of insects, all lack a key enzyme that is required to convert a sugar, glucose, into vitamin C.
No single bacterial genus or species is known that will carry out all of the reactions needed to synthesize vitamin C, but there are two (Erwinia species and Corynebacterium genus) that, between them, can perform all but one of the required steps. In 1985 a gene from one of these genus (Corynebacterium ) was introduced into the second organism (Erwinia herbicola ), resulting in a new bacterial form. This engineered organism can be used to produce a precursor to vitamin C that is converted via one chemical reaction into this essential vitamin. The engineering of many other microorganisms is being used to replace complex chemical reactions. For example, amino acids , needed for dietary supplements, are produced on a large scale using genetically modified microorganisms, as are antibiotics.
Another important class of compounds produced by biotechnology is enzymes . These protein catalysts are used widely in both medical and industrial research. Proteases, enzymes that break down proteins, are particularly important in detergents, in tanning hides, in food processing, and in the chemical industry. One of the most significant commercial enzymes of this type is subtilisin, which is produced by a bacterium. Because many stains contain proteins, the manufacturers of laundry detergents include subtilisin in their product. Subtilisin is 274 amino acids long, and one of these, the methionine at position 222, lies right beside the active site of the enzyme. This is the site on the enzyme's surface where the substrate is bound, and where the reaction that is catalyzed by the enzyme takes place. In this instance the substrate is a protein in a stain, and the reaction results in the breaking of a peptide bond in the backbone of the protein. Unfortunately, methionine is an amino acid that is very easily oxidized , and laundry detergents are often used in conjunction with bleach, which is a strong oxidizing agent. When used with bleach, the methionine in subtilisin is oxidized and the enzyme is inactivated, preventing the subtilisin from doing its work of breaking down the proteins present in food stains, blood stains, and the like.
To overcome this problem, genetic engineering techniques were used to isolate the gene for subtilisin, and the small part of the gene that codes for methionine 222 was replaced by chemically synthesized DNA fragments that coded for other amino acids. The experiment was done in such a way that nineteen new subtilisin genes were produced, and every possible amino acid was tried at position 222. Some of the altered genes gave rise to inactive versions of the enzyme, but others resulted in fully functional subtilisin. When these subtilisins were tested for their resistance to oxidation, most were found to be very good (except when cysteine replaced methionine: It too is easily oxidized). So now it is possible to use laundry detergent and bleach at the same time and still remove protein-based stains. This type of gene manipulation, which has been called "protein engineering," has already been used for making beneficial changes in other industrial enzymes, and in proteins used for medical purposes.
Biotechnology companies are continuing to produce new products at an impressive rate. Numerous clinical testing procedures for human disorders such as AIDS and hepatitis and for disease-causing organisms such as those responsible for malaria and Legionnaires' disease (a lung infection caused by the bacterium Legionella pneumophila ), are based on diagnostic testing kits that have been developed by biotechnology companies. Many of these assays make use of recombinant antibodies , while others rely on DNA primers that are used in the polymerase chain reaction to detect DNA sequences present in an infecting organism, but not in the human genome.
Trangenic plants are now grown on millions of acres. Many of these plant species have been engineered to produce a protein, normally synthesized by the bacterium Bacillus thuringiensis, which is toxic to a number of agriculturally destructive insect pests but harmless to humans, most other non-insect animals, and many beneficial insects such as bees.
Like all industries, the biotechnology industry is subject to rules and regulations. Legal, social, and ethical concerns have been raised by the ability to genetically alter organisms. These have resulted in the establishment of governmental guidelines for the performance of biotechnology research, and specific requirements have been set to control the introduction of recombinant DNA products into the marketplace. General governmental guidelines for biotech research are published on the Internet at http://www.aphis.usda.gov/biotech/OECD/usregs.htm. Guidelines for plant genetic engineering and biotechnology are available at http://sbc.ucdavis.edu/Outreach/resource/US_gov.htm.
see also Agricultural Biotechnology; Biotechnology and Genetic Engineering, History of; Cloning Genes; Cloning Organisms; Gene Therapy; Genetic Testing; Genetically Modified Foods; Hemophilia; Polymerase Chain Reaction; Recombinant DNA; Transgenic Animals; Transgenic Microorganisms; Transgenic Plants.
Dennis N. Luck
Glick, Bernard R., and Jack J. Pasternak. Molecular Biotechnology: Principles and Applications of Recombinant DNA. Washington, DC: ASM Press, 1998.
Marx, Jean L. A Revolution in Biotechnology. Cambridge, MA: Cambridge University Press, 1989.
Primrose, S. B. Molecular Biotechnology. Boston: Blackwell Scientific Publications, 1991.
Rudolph, Frederick B., and Larry V. McIntire, eds. Biotechnology: Science, Engineering, and Ethical Challenges for the Twenty-first Century. Washington, DC: Joseph Henry Press, 1996.
Before Captain James Cook, the famous English sailor and navigator, had his men drink lime juice (which contains vitamin C) during extended sea voyages, many sailors fell ill or died of the vitamin C deficiency known as scurvy.
The early years of the ‘new’ biotechnology focused on the technologies required to clone, overexpress, purify, and administer biopharmaceuticals such as insulin, growth hormone, factor VIII (deficient in haemophilia), and erythropoietin, with some 200 other proteins currently in the pipeline. However, in the future, the most significant breakthroughs in human medicine will result from mapping and understanding the human genome — in elucidating the exact sequence of the billions of nucleotides that constitute the estimated 30 000–40 000 genes that are the collective blueprint for human beings and are responsible for some 10 000 genetic disorders. The Human Genome Project was launched in 1990 as a 15-year, $3 billion international effort to map and sequence all human genes. Innovations in sequencing technology have ensured that the project moved ahead of schedule. With less than 5% of all human genes identified at the start of the project, it has become increasingly clear that each new gene discovery proffers new drugs for the diagnosis, treatment, and prevention of human disease. These drugs include therapeutic proteins, diagnostics, gene therapy reagents, and small molecules. A significant proportion of the human genome has been sequenced and many new human disease genes are being characterized. These advances will enable biotechnologists not only to measure disease potential and expand the applications for genomic diagnostics but also to devise fundamental new therapeutic approaches.
Genomics and genetic engineering are also playing a substantial role in the development of agricultural biotechnology. This sector is finally moving out from under the shadow of the biopharmaceutical community and is now competing in terms of publicity and investor attention. This is because $1 billion is considered an attractive market in the biopharmaceutical industry, whilst global agricultural markets can readily top $10 billion and the total end-use value of food, fibre, and biomass is estimated to be over $1500 billion. The addressable market on which value can be added and costs cut is at least 6–7 times that of its pharmaceutical counterpart. Two of the factors that have encouraged biotechnologists to enter the genetically engineered food and plant arena are the desire of consumers for better tasting foods and a preference for products grown using fewer pesticides. Calgene was the first company to market a genetically improved tomato which could be ripened on the vine without softening and thereby result in improved taste and texture. Antisense technology was used to inhibit the enzyme polygalacturonase which degrades pectin in the cell wall. Similarly, laurate Canola is the world's first oilseed crop that has been genetically engineered to modify oil composition. Laurate is the key raw material used in the manufacture of soap, detergent, food, oleochemical, and personal care products. Other examples of transgenic agricultural crops include high stearate and myristate oils, low saturate oils, high solids tomatoes and potatoes, sweet minipeppers, modified lignin in paper pulp trees, pesticide-resistant plants, and biodegradeable plastics.
The early goals in the development of transgenic livestock were the increase of the meat and of the production characteristics of food animals. However, long research and development timelines and low projected profit margins, especially in developed nations where food is relatively inexpensive, have shifted priorities to the production of protein pharmaceuticals and nutraceuticals in the milk of transgenic animals. Milk has a high natural protein content and is sequestered in a gland where its proteins exert little direct systemic effect. It provides a renewable production system that is capable of complex and specific ‘post-translational processing’: that is, modifications to the protein that occur after it has been synthesized as a polypeptide (such as conjugation with carbohydrate moieties), which can alter the biological or therapeutic properties of the protein. Such changes cannot easily be accomplished in conventional cell culture systems. As a result, the ‘biopharming’ focus has shifted to the production of human blood plasma proteins and other therapeutic proteins, in ruminants such as cows, sheep, and goats which are easy to milk.
Marine organisms are also capable of producing a variety of polymers, adhesives, and compounds for cosmetics and food preparation. Bioactive natural products are found in organisms that reside in areas which stretch from easily accessible intertidal zones to depths in excess of 1000 m. Collaborations between marine chemists, molecular pharmacologists, and cell biologists have yielded an impressive library of potentially useful cancer, viral, antibiotic, anti-inflammatory, cardiovascular, and CNS drugs.
The pharmaceutical, agrichemical, and speciality chemical industries are increasingly requiring molecules which have distinct left- or right-handed forms, so-called chiral compounds. Whilst chemical and biological techniques for producing single left- or right-handed forms are developing apace, it is apparent that no single approach is likely to dominate. Suppliers and customers alike must continue to draw upon the entire range of chemical, enzymatic, and whole-organism tools that are available to produce chiral compounds. Unfortunately, only 10% of the 25 000 or so enzymes found in nature have been identified and characterized, and, of these, only 25 are produced in large quantities. Despite some duplication in activity among enzymes, there is a need to characterize more in order to exploit their unique specificity and activity. However, barriers to enzyme scale-up include product inhibition and a general reluctance on the part of chemists to use water-based reagents in systems which are traditionally non-aqueous. Consequently, enzymes should be made more user-friendly both for bench chemists exploring novel synthetic strategies and for all stages in pharmaceutical scale-up. However, the biologists' toolbox for catalysis is expanding. For decades, there were only two types of catalyst — metals and enzymes — but since 1986 two new classes of biocatalyst have emerged along with the enzymes, ribozymes, and catalytic antibodies. These novel biocatalysts are prepared both by classical biochemical and immunological methods and by recombinant and phage display technologies. Whilst there are still many catalysts still to be discovered, such biocatalysts will have to exhibit improved performance, stability, turnover numbers, specificity, and product yields.
Biotechnology is also playing a role in ‘clean’ manufacturing. Nevertheless, various types of chemical manufacturing, metal plating, wood preserving, and petroleum refining industries currently generate hazardous wastes, comprising volatile organics, chlorinated and petroleum hydrocarbons, solvents, and heavy metals. Bioremediation with microbial consortia is being investigated as a means of cleaning up hazardous sites. Methods include in situ and ex situ treatment of contaminated soil, groundwater, industrial wastewater, sludges, soil slurries, marine oil spills, and vapour-phase effluvia.
Biotechnology is expected to contribute massively to the global economy, largely through the introduction of recombinant DNA technology to the production of biopharmaceuticals. In the future, biotechnology will concentrate on the complexity and interrelatedness of biology, with such targets as the human genome project; genetic medicine; gene and cell therapy; tissue engineering; vaccines; factors for transcribing DNA into RNA; signal transduction and the control of gene expression; managing ageing at the level of programmed cell death, and genes that control cell division; neurobiotechnology; agri-industrial biotechnology; drug delivery; cell adhesion and communication; and novel diagnostics. Needless to say, and subject to clarification of certain ethical and public acceptance issues, biotechnology is set to make an indelible contribution to human health and welfare well into the foreseeable future.
C. R. Lowe
Biotechnology is the use of any technique involving living organisms to manufacture or change products, to improve the desired characteristics of a plant or animal , or to alter microorganisms for a purpose.
Biotechnology has a long history. For example, yeast microorganisms were harnessed to prepare wine by Egyptians some 4,000 years before the birth of Christ. In 1865, Gregor Mendel presented his laws of heredity, which he deduced by the careful observation of the results of breeding different types of pea plants. Although he did not realize it at the time, Mendel was observing the results of the exchange and altered expression of genetic material.
The modern day conception of biotechnology, with the deliberate experimental manipulation of genetic material, had its roots in the mid years of the twentieth century. In 1940, deoxyribonucleic acid (DNA) was isolated by Oswald Avery. Thirteen years later, James Watson and Francis Crick described the double helix structure of DNA, a feat that earned them a Nobel Prize just a few years later. The modern age of biotechnology began in 1973, when Stanley Cohen and Herbert Boyer devised recombinant DNA technology; the deliberate introduction of DNA from one species into another. Their work made possible feats such as the production of human insulin by the bacterium Escherichia coli . This genetically engineered human insulin was, in fact, the first genetically engineered product approved for sale in the United States in 1982.
The latter decades of the twentieth century saw an explosion in the experimental and commercial use of biotechnology.
The basic concept of biotechnology involves recombination, or the process where genetic material from just about any living organism can be isolated, cut up into pieces using special enzymes, and the pieces encouraged to recombine. The recombination can be between genetic material from the same organism, or between genetic material from different organisms. Differences between the organization of the genetic material of organisms like bacteria and "higher" organisms such as humans, and the difference in how the genetic traits coded for by the material are expressed, has complicated the advances in biotechnology. But, increasingly, such species differences are being understood.
Applications of biotechnology are numerous. For example, foods are being genetically altered to engineer in more nutritional compounds. The nutraceutical industry is growing to become a potent economic force, generating billions of dollars in sales each year in the United States alone. Genetic manipulation can also help preserve foods longer, allowing a fresher product to reach the supermarket shelves.
An aspect of biotechnology that has garnered much attention since the 1990s is cloning. Until 1997, a fully developed organism could not be cloned. But, in early 1997, the first success at producing live animals by embryo cloning occurred in Edinburgh, Scotland. The procedure that produced Dolly the sheep was reported in the March 6, 1997 edition of Nature.
While embryo cloning is still a "hit or miss" procedure, the consensus among researchers involved in embryo cloning is that cloning animal embryos will be perfected. The resulting ease of genetic tailoring could produce higher yielding and disease-resistant livestock .
Cloning embryos is similar to what happens naturally when identical twins are created in the womb. All human embryos begin as a single cell . Normally, millions of rounds of division and the formation of cells that differ in structure and function from other cells gives rise to a human. With identical twins, as the cell divides it separates into two separate, individual cells. The two separate, individual cells then divide and differentiate independently. The result is two embryos that are identical in the composition of their genetic material.
In embryo cloning, a cell is mechanically encouraged to divide into two separate, individual cells. These grow and develop separately, creating identical twins.There is continuing debate around the moral and ethical limits on cloning human embryos. Currently, it is illegal to use federal research funds in the United States to clone human embryos.In November of 2001, the human cloning debate was raised from a theoretical discussion to a concrete discussion. Then, a company in suburban Boston announced that a human cell had been cloned to provide stem cells for research. While the experiment was carried on for only a few cell divisions, the technology required to develop a cloned human being may be almost in place.
The prospects offered by biotechnology have not been greeted with unanimous enthusiasm by everyone. Many scientists and laypersons assert that the hope of curing or avoiding genetic disorders through biotechnology is a positive advance. Some hold that the genetically derived nutritional enhancement of foods, such as the nutritional supplementation of rice grown in developing countries, is a worthy aim. Others oppose all forms of genetic engineering , or warn of the dangers of having such technology as the commercial property of a few large companies. There are also concerns about genetic privacy, the effects of transgenic organisms on other organisms and the environment, and animal rights.
As the technology available for genetic engineering continues to improve, debates over the use of these techniques in practical settings are almost certainly going to continue and escalate in the future.
Charles, D. Lords of the Harvest: Biotech, Big Money, and theFuture of Food. Cambridge, MA: Perseus Books, 2001.
Wilmut, I., K. Campbell, and C. Tudge. The Second Creation:Dolly and the Age of Biological Control. New York: Farrar, Straus and Giroux, 2000.
Lerner, J., and R.P. Merges, 1998, "The Control of Technology Alliances: An Empirical Analysis of the Biotechnology Industry." Journal of Industrial Economics 66 (June 1998): 125–-156.
Martin, G.B., S.H. Brommonschenkel, J. Chunwongse, et al., "Map-based Cloning of a Protein Kinase Gene Conferring Disease Resistance in Tomato." Science 262 (1993): 1432–1436.
KEY TERMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
—Development of new breeds of plants or animals achieved by combining the desired traits of two or more species in controlled breeding.
- Recombinant DNA research
—A process of DNA modification by which two different DNA molecules are combined.
Biotechnology research in space is predicated on understanding and exploiting the effects of the unique microgravity environment on chemical and biological systems. The results of these experiments could point the way not only to commercial enterprises in space but also to new research directions for laboratories on Earth. Protein crystallization and cell biology are two areas in which microgravity research is particularly promising.
Researchers are interested in determining the structure of proteins because the twists and folds of these complex molecules provide clues to their specific functions and how they have evolved over time. However, for scientists to study their structures, the molecules must be "held in place" through crystallization. Large, good-quality crystals are valued by structural biologists, but some organic molecules are easier to crystallize than others are. In some cases the resolution of important biological questions awaits the ability to produce adequate crystals for structural analysis.
For more than fifteen years it has been known that with other conditions being equal, protein crystals grown in a microgravity environment are larger than those grown on Earth. However, the impact of this realization has been limited because of the irregular, short-term nature of space shuttle flights and the lack of a permanent laboratory with adequate vibration control.
Facilities aboard the International Space Station (ISS) may be able to address this need. Even if there is only an incremental increase in quality when crystals are produced in orbiting rather than Earth laboratories, that increase may make the difference in terms of being able to determine the structure of some proteins, providing new knowledge of biological mechanisms. An X-ray crystallography facility planned for the ISS would provide robotic equipment not only for growing the crystals but also for initial testing. Only the most promising specimens would be stored in the station's limited freezer space to be brought back to Earth aboard a shuttle.
Cell biology is another area in which space-based research may produce valuable findings. In this case the key attribute of the microgravity environment is the ability to grow three-dimensional cell cultures that more closely mimic the way the cells would behave in the organism.
When cells are grown, or "cultured," for experiments on Earth, gravity encourages them to spread out in two-dimensional sheets. For most tissues this is not a particularly realistic configuration. As a result, the interactions between the cells and the biological processes within them are different from what would be seen in nature. At a molecular level this is seen as differences in gene expression, the degree to which a particular gene is "turned on" to make a protein that serves a specific function in the organism.
In a microgravity environment it is easier to get the cells to adopt the same three-dimensional form that they have during normal growth and development. This means that the gene expression pattern in the cultured cells is more like the pattern that occurs in nature. In addition, it suggests the possibility of culturing not only realistic three-dimensional tissues but entire organs that could have both research and clinical applications.
Because of the potential importance of this work, scientists have attempted to duplicate the microgravity environment on Earth. They have done this by placing tissue cultures in rotating vessels called bioreactors where the centrifuge effect cancels out the force of gravity.
Some success has been experienced with small cultures when the rotating vessel technique has been used. However, as the cultures grow larger, the vessel must be spun faster and faster to balance out their weight and keep them in suspension. At that point rotational effects such as shear forces damage the cells and cause their behavior to diverge from what is seen in the organism. This is a problem that could be solved if the experiments were done in space.
Technology and Politics
However, in considering the potential for biotechnology in space, it is important to understand the technological and political context. Researchers are making rapid progress in both protein crystallization and three-dimensional tissue culture in laboratories on Earth, generally at significantly lower cost than that associated with space programs. Any perception that coveted research funds are being diverted to space-based programs without adequate justification causes resentment of such programs within the scientific community.
In addition, the difficulties of funding a large, expensive space station over the many years of planning and construction have resulted in numerous changes to the ISS's design, facilities, and staffing. Refrigerator and freezer space, for example, has been reduced, creating a potential problem for biology research. Exacerbating the problem is uncertainty in the schedule on which shuttles will be available to transport specimens. Another change of major concern to scientists contemplating participation in the program is a possible reduction in crew size, at least initially, from the planned complement of ten to a "skeleton crew" of only three.
The reduced crew size drastically limits the ability of astronauts to assist with the research, meaning that the experiments that will be flown must require little to no local human intervention. However, the overall budget instability also has affected hardware development funds so that it is more difficult to provide the advanced automation, monitoring, and ground-based control capabilities that are needed.
There are promising applications for biotechnology in the microgravity of space. However, the extent to which these applications will be realized depends on whether they are seen to accelerate the pace of research or whether the situation is viewed as a "zero-sum game" in which resources are diverted that might be better used on Earth. Finally, it remains to be seen whether the political and economic climate will result in an orbiting platform with the staffing and facilities needed to address real research needs.
see also Crystal Growth (volume 3); International Space Station (volumes 1 and 3); Microgravity (volume 2); Resource Utilization (volume 4); Space Stations of the Future (volume 4).
Sherri Chasin Calvo
National Academy of Sciences. Future Biotechnology Research on the International Space Station. Washington, DC: National Academies, 2001.
"Success Stories: Biotechnology."NASA Space Product Development. <http://www.spd.nasa.gov/biotech.html>.
Biotechnology is the application of biological processes in the development of products. These products may be organisms, cells, parts of a cell, or chemicals for use in medicine, biology, or industry.
History of biotechnology
Biotechnology has been used by humans for thousands of years in the production of beer and wine. In a process called fermentation, microorganisms such as yeasts and bacteria are mixed with natural products that the microorganisms use as food. In winemaking, yeasts live on the sugars found in grape juice. They digest these sugars and produce two new products: alcohol and carbon dioxide.
Early in the twentieth century, scientists used bacteria to break down, or decompose, organic matter in sewage, thus providing a means for dealing efficiently with these materials in solid waste. Microorganisms were also used to produce various substances in the laboratory.
Hybridization—the production of offspring from two animals or plants of different breeds, varieties, or species—is a form of biotechnology that does not depend on microorganisms. Farmers long ago learned that they could produce offspring with certain characteristics by carefully selecting the parents. In some cases, entirely new animal forms were created that do not occur in nature. An example is the mule, a hybrid of a horse and a donkey.
Hybridization has also been used for centuries in agriculture. Most of the fruits and vegetables in our diet today have been changed by long decades of plant crossbreeding. Modern methods of hybridization have contributed to the production of new food crops and resulted in a dramatic increase in food production.
Words to Know
DNA (deoxyribonucleic acid): A nucleic acid molecule (an organic molecule made of alternating sugar and phosphate groups connected to nitrogen-rich bases) containing genetic information and located in the nucleus of cells.
Hybridization: The production of offspring from two parents (such as plants, animals, or cells) of different breeds, species, or varieties.
Monoclonal antibody: An antibody produced in the laboratory from a single cell formed by the union of a cancer cell with an animal cell.
Recombinant DNA research (rDNA research): A technique for adding new instructions to the DNA of a host cell by combining genes from two different sources.
Discovery of DNA leads to genetic engineering
The discovery of the role of deoxyribonucleic acid (DNA) in living organisms greatly changed the nature of biotechnology in the second half of the twentieth century. DNA, located in the nucleus of cells, is a complex molecule that stores and transmits genetic information. This information provides cells with the directions to carry out vital bodily functions.
With the knowledge of how genetic information is stored and transmitted, scientists have developed the ability to alter DNA, creating new instructions that direct cells to produce new substances or perform new functions. The process of DNA alteration is known as genetic engineering. Genetic engineering often involves combining the DNA from two different organisms, a technique referred to as recombinant DNA research.
There is little doubt that genetic engineering is the best known form of biotechnology today, with animal cloning and the Human Genome Project making headlines in the news. Indeed, it is easy to confuse the two terms. However, they differ in the respect that genetic engineering is only one type of biotechnology.
Another development in biotechnology is the discovery of monoclonal antibodies. Monoclonal antibodies are antibodies produced in the laboratory by a single cell. The single cell is formed by the union of two other cells—a cancer cell and an animal cell that makes a particular antibody. The hybrid cell multiplies rapidly, making clones of itself and
producing large quantities of the antibody. (Antibodies are chemicals produced in the body that fight against foreign substances, such as bacteria and viruses.) Monoclonal antibodies are used in research, medical testing, and for the treatment of specific diseases.
[See also Clone and cloning; Endangered species; Fermentation; Genetic engineering; Human Genome Project; Nucleic acid ]