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Date: 2015-10-07; view: 488.

The apparently successful cloning of an adult mammal, announced in 1997 by a team of Scottish scientists led by Ian Wilmut, raised a number of ethical issues. The cloned mammal, a sheep named Dolly, seemed to open the theoretical possibility that human beings could also be cloned. Immediately after Dolly's existence was announced, politicians in several countries called for a ban on scientific research into human cloning. In this article British philosopher Mary Warnock warns against letting the fear of cloning cripple the future of scientific research into its possibilities.

By Mary Warnock

On March 7, 1996, the periodical Nature carried an account of the cloning of a sheep by the use of a new technique, at the Roslin Institute near Edinburgh. A year later the same periodical had the story of the one successful live birth resulting from the experiment (29 births had been attempted), of a lamb now six months old, known as Dolly. The birth of Dolly, without a father, from the extraction of a cell from an adult female sheep, caused a great sensation in the media. And meanwhile other experiments had been taking place, notably the cloning, by a different technique, of monkeys in a private research institute in Oregon. The inevitable question was raised. If other mammals can be cloned, why not humans? Apart from the extreme difficulty of the processes involved, and their low success rate (which would surely improve with time) what was to stand in the way of humans being born, with chosen genetic qualities, from the tissue of another adult human?

The answer must be that the cloning of humans is, or will be, possible. Why, then, do we react so strongly and immediately against the thought? The first thing to be said is that we are perfectly accustomed to genetic clones. We do not react with horror or distaste from naturally formed identical twins. And identical twins are in fact closer, genetically, to one another than Dolly is to her originating parent, of whom she is the clone. For identical twins share all their genes. Dolly, on the other hand, is the result of the nucleus of a cell from her “parent” sheep; and the cytoplasm contains few but significant genes of its own, including the mitochondria, mutations in which can cause horrendous diseases in humans. Dolly therefore possesses some genes that came not from her “parent” but from the donor of the egg which received the nucleus from the “parent.” Strictly speaking, therefore, she is not identical with that parent.

In any case, since we recognize that identical twins, or natural clones, are distinct human individuals, with lives of their own, in no way deprived of freedom or dignity or personal identity, it cannot be genetic identity that appalls us. There must be some other source of the fear that grips people who think of human cloning.

There are certainly odd features of Dolly. For one thing, she has no father. She came into the world as the result of a pregnancy started by the removal of tissue from an adult female. Some people may be alarmed that this method of cloning could remove the need for a father in the life of a child. Another oddity of Dolly is that parts of her seem to be of a different age from other parts. The nucleus that came from her “parent” is adult; but her mitochondria give her the ordinary status of the newborn. It is uncertain how she will age.

The main source of anxiety, however, is the degree of intervention required to make a clone, and the opportunity that this opens up for changing the genetic makeup of the resulting human. Some people have welcomed the birth of Dolly on the grounds that it makes possible the quick generation of improved farm animals. But of course, if this is a valid argument, then, equally, we could see the quick generation of an “improved” kind of human being, with characteristics specially chosen to be useful or trouble-free to politicians; or even to be better according to some neo-Aristotelian criterion of what constitutes the best kind of person to be.

This fear is a part of our general fear of being used or manipulated for someone else's ends. The belief that each human individual is of infinite value, intrinsically, is bound up with two further beliefs. The first is that how we are, each one of us, is partly a matter of chance, of the mixture of genes we happen to have inherited from our parents. The second belief is that we are able to choose for ourselves how we live, whether to improve ourselves, whether to rebel against our background, or accept it and incorporate it in our own chosen way of life. It is worth raising the question how much of this would be lost to us if we were born as a result of cloning.

The fact is that not very much would be lost. We would perhaps not have been born with a chance mixture of genetic inheritance, but we would be as much or as little free as we are now. We would still, as we are now, be largely shaped by the chances of our environment, not just our physical environment, but whom we happen to meet, whom we got to know at school, who taught us, where we went on holiday; all the things that shape us now would shape us then. Are we rational, then, to be so much afraid?

The answer may well be that we are not. And there is a further point to be made. The fear of human cloning may be seen as the fear that somehow someone will become politically so powerful as to treat humans like cattle, or racehorses, and hope to produce the best breed of humans as he might try for the best breed of cattle. In fact to produce even cattle by asexual cloning would be a deeply mistaken policy. The diversity produced by ordinary, and chancey, reproduction will always be preferable, even among cattle (or racehorses) although it may seem that there is just one specific function that these animals are supposed to fulfill. The diversity of the gene pool is a safeguard against the development of genetic defects that might lead to the weakening, even the destruction of the whole species. It is doubtful therefore whether anyone would be so foolish, even if they could conceivably become powerful enough to embark on large-scale cloning of humans.

If we can put this great fear from our minds, it remains to ask whether there are any circumstances in which cloning might be a chosen way of birth, not for huge numbers of the human race, but for the occasional individual. It seems possible that there might be some kinds of male infertility where the nucleus of a cell from an adult male might be used for merging with, or placing within the cytoplasm of an egg, which could then be implanted in the female partner's uterus. But, more importantly, there is at the present time a great deal that is not known about the early development of differentiated cells and the part that the nucleus and the cytoplasm play in the development of the embryo. Research into these matters is likely to be of enormous importance in finding ways to combat genetically inherited disease. From the point of view of medical knowledge and the conquest of disease, it would seem to be important that it should be legally permissible to fertilize human cells by cloning, whether for the purposes of observation only, or for the development of drugs.

A number of countries already have laws in place that prohibit the cloning of humans. It is possible that the birth of Dolly may make some countries nervously introduce such legislation, others perhaps tighten up the laws they have. However, such measures should be taken with a realistic eye to what the dangers actually are. No one would doubt that human cloning should be regulated, in order to criminalize not only the mad dictator, but the quack doctor who may promise what it is impossible to perform. Yet the potential advantages to science and medicine, and therefore to humans as a species must not be overlooked, or forgotten in hysteria and panic.

Learn the new words from the text on cloning

to enable smb. to do smth.

to be coaxed

breeding techniques

to devise

to bolster

endangered (extinct) species

environmental contamination

to generate smth.

genetically modify

identical offspring

irreversible side effects

to pose risks

to be replicated

to capture the attention of the scientific community

to duplicate

to manipulate human genetic makeup

to stand in the way of smth.

horrendous

to appal

to be bound up with smth.

to combat smth.

to tighten up (the laws)

A different way of breeding a “perfect man” is called eugenics, a study which involves changes on the genetic level. Read the text, paying your attention to the new words, and learn how it differs from cloning.

WHAT IS GENETICS?

Genetics is study of the function and behavior of genes. Genes are bits of biochemical instructions found inside the cells of every organism from bacteria to humans. Offspring receive a mixture of genetic information from both parents. This process contributes tothe great variation of traits that we see in nature, such as the markings on a butterfly's wings, or such human behavioral traits as personality or musical talent. Geneticists seek to understand how the information encoded in genes is used and controlled by cells and how it is transmitted from one generation to the next. Geneticists also study how tiny variations in genes can disrupt an organism's development or cause disease. Increasingly, modern genetics involves genetic engineering, a technique used by scientists to manipulate genes. Genetic engineering has produced many advances in medicine and industry, but the potential for abuse of this technique has also presented society with many ethical and legal controversies.

Genetic information is encoded and transmitted from generation to generation in deoxyribonucleic acid (DNA). DNA acids are complex molecules produced by living cells and are essential to all living organisms. These acids govern the body's development and specific characteristics by providing hereditary information and triggering the production of proteins within the body. Although all humans share the same set of genes, individuals can inherit different forms of a given gene, making each person genetically unique.

Since the earliest days of plant and animal domestication, around 10,000 years ago, humans have understood that characteristic traits of parents could be transmitted to their offspring. The first to speculate about how this process worked were Greek scholars around the 4th century bc, who promoted theories based on conjecture or superstition. Some of these theories remained in favor for several centuries. The scientific study of genetics did not begin until the late 19th century. In experiments with garden peas, Austrian monk Gregor Mendel described the patterns of inheritance, observing that traits were inherited as separate units. These units are now known as genes. Mendel's work formed the foundation for later scientific achievements that heralded the era of modern genetics.

GENES AND SOCIETY

Genetic Engineering is alteration of an organism's genetic, or hereditary, material to eliminate undesirable characteristics or to produce desirable new ones. Genetic engineering is used to increase plant and animal food production; to diagnose disease, improve medical treatment, and produce vaccines and other useful drugs; and to help dispose of industrial wastes. Included in genetic engineering techniques are the selective breeding of plants and animals, hybridization (reproduction between different strains or species), and recombinant deoxyribonucleic acid (DNA).

Advances in genetic technologies allow scientists to take an unprecedented glimpse into the genetic makeup of every person. The information derived from this testing can serve many valuable purposes: It can save lives, assist couples trying to decide whether or not to have children, and help law-enforcement officials solve a crime. Yet breakthroughsin genetic testing also raise some troubling social concerns about privacy and discrimination. For example, if an individual's genetic information becomes widely available, it could give health insurers cause to deny coverage to people with certain risk factors or encourage employers to reject certain high-risk job applicants. Furthermore, many genetically linked problems are more common among certain racial and ethnic groups. Many minority groups fear that the expansion of genetic testing could create whole new avenues of discrimination.

Of particular concern are genetic tests that shed light on traits such as personality, intelligence, and mental health or potential abilities. Genetic tests that indicate a person is unlikely to get along with other people could be used to limit a person's professional advancement. In other cases, tests that identify a genetic risk of heart failure could discourage a person from competing in sports.

New technologies that allow the manipulation of genes have raised even more disturbing possibilities. Gene therapy advances, which allow scientists to replace defective genes with normal alleles, give people with typically fatal diseases new hope for healthy lives. To date, gene therapy has focused on manipulating the genetic material in body cells other than gametes, so the changes will not be passed on to future generations. However, the application of gene therapy techniques to gametes—the cells involved in reproduction—seems inevitable. Such manipulation might help prevent the transmission of disease from one generation to another, but it could also produce unforeseen problems with long-lasting consequences.

For instance, many people worry that new genetic techniques could be used to alter or encourage traits now viewed as part of normal human variability, such as shortness or baldness. At various times in the past century, people have advocated efforts to improve the human condition by promoting the perpetuation of certain genes. This concept, known as eugenics, typically involves encouraging people with “positive” genes to reproduce and discouraging those with “inferior” genes from having offspring. Many people fear that new genetic technologies used to manipulate the human genome could give people previously unattainable methods to resort to extreme forms of eugenics.

Advances in genetic technologies have turned some genes into valuable commercial commodities, spawning a host of controversial questions. Who owns a genetically altered organism or the genes it contains? Is it right to patent the use of a naturally occurring gene? Some people feel that genetic material should not be owned or used for profit. Balancing the need to limit patents on genes are concerns that the profit motive of companies must be protected to maintain incentives to make new discoveries for medical products.

EUGENICS

British scientist Sir Francis Galton is perhaps best known as the founder of eugenics, a science devoted to the principle that the hereditary characteristics of human beings can be “perfected” through controlled mating. As part of his extensive research into heredity, Galton measured and recorded selected hereditary characteristics of a large number of people. This effort piqued Galton's interest in the variation between human fingerprints, leading him to develop a rudimentary fingerprint identification system.

Although the idea of eugenics is contained in Plato's Republic, the modern concept became prominent during the second half of the 19th century. Underlying this interest in eugenics were two widespread philosophical convictions: a belief in the perfectibility of the human species and a growing faith in science as the most dependable and useful form of knowledge. One 19th-century predecessor of 20th-century eugenics was the group of sociological theories known as social Darwinism. The favorite catchwords of social Darwinism—“struggle for existence” and “survival of the fittest”—when applied to humans in society, suggested that the rich were better endowed than the poor and hence more successful in life. The continual and natural sorting out of “better” and “worse” elements would therefore lead to continued improvement of the species. Modern eugenics has its roots in, but differs from, social Darwinism. The latter was characterized by its laissez-faire attitude, that is, allowing nature to take its course so that the worst elements of society would eventually be eliminated. Modern eugenics, on the other hand, is based on the notion that careful planning through proper breeding is the key to bettering society.

THE CONTROVERSY OVER GENETICALLY ENGINEERD FOOD

In the late 20th century scientists devised methods of altering the genetic makeup of food crops. Humans have modified crops for thousands of years to increase yield and resistance to pests, but changes on the molecular level have caused some people to wonder if science has gone too far. Recent studies suggest that some genetically altered crops may pose health risks and other dangers. Proponents of genetically modified food, however, point to increased yields and health benefits.

Human efforts to modify food crops are not new. In the first 10,000 years or so that people planted and harvested crops, they steadily cultivated hardier varieties by saving and replanting seeds from their best plants. Selective breeding, in use by about 5000 BC, gave farmers another tool to improve their crops. Improvements came slowly but were eventually substantial. The scientific revolution ushered in by the Renaissance encouraged experimentation in selective breeding and quickened the pace of change. Many of the world's global food staples have changed so much that they would not be recognizable to ancient tillers of the soil.

In recent years the once staid and steady field of farming began to change with extraordinary speed. These changes are driven by developments in molecular genetics, which have given scientists unprecedented control over a plant's individual genes. Genes are the basic units of heredity that determine the particular characteristic or group of characteristics that an organism inherits.

Before the era of biotechnology, farmers crossed related plant varieties to create hybrid strains and selectively bred the offspring of these hybrids to produce desirable traits. This form of genetic modification naturally limits genetic variation because only closely related plants can be bred. In the new world of agricultural biotechnology, scientists are no longer constrained by barriers between species. They can take genes from entirely unrelated organisms—viruses, bacteria, even fish and other animals—and splice them directly into plants. In doing so, they are redefining the very nature of the crops upon which humanity has long depended.

Supporters of genetically engineered food have put forward a bold vision for the new agricultural biotechnology. They see a world in which key food crops will be genetically altered to offer better nutrition, repelpests, and flourish in hostile environments—a world in which food is plentiful and hunger scarce. This vision, however, is not universally shared. Some farmers, consumers, environmentalists, and governments have expressed concern that genetically engineered crops pose substantial risks to human health, the environment, and rural economies. By the late 1990s, these concerns had provoked a polarized and rancorous global debate that shows no sign of ending soon.

Learn the new words from the text on genetics