StemCell Therapy

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 (18091882), 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.

In the twentieth century, as biologists refined Darwin's proposal and explored its relationship to genetics, plant breeders such as Luther Burbank (18491926) 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.

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 Dollythe transfer of the nuclear DNA from an adult cell to an egg, thereby creating an embryo and starting it through its own developmental processcan 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 germlinethat 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 testingto identify the sex of the unborn and to abort femalesis 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.

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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ronald cole-turner

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