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Clones are organisms that are exact genetic copies. Every single bit of their DNA is identical.

Clones can happen naturallyidentical twins are just one of many examples. Or they can be made in the lab. Below, find out how natural identical twins are similar to and different from clones made through modern cloning technologies.

Many people first heard of cloning when Dolly the Sheep showed up on the scene in 1997. Artificial cloning technologies have been around for much longer than Dolly, though.

There are two ways to make an exact genetic copy of an organism in a lab: artificial embryo twinning and somatic cell nuclear transfer.

Artificial embryo twinning is a relatively low-tech way to make clones. As the name suggests, this technique mimics the natural process that creates identical twins.

In nature, twins form very early in development when the embryo splits in two. Twinning happens in the first days after egg and sperm join, while the embryo is made of just a small number of unspecialized cells. Each half of the embryo continues dividing on its own, ultimately developing into separate, complete individuals. Since they developed from the same fertilized egg, the resulting individuals are genetically identical.

Artificial embryo twinning uses the same approach, but it is carried out in a Petri dish instead of inside the mother. A very early embryo is separated into individual cells, which are allowed to divide and develop for a short time in the Petri dish. The embryos are then placed into a surrogate mother, where they finish developing. Again, since all the embryos came from the same fertilized egg, they are genetically identical.

Somatic cell nuclear transfer (SCNT), also called nuclear transfer, uses a different approach than artificial embryo twinning, but it produces the same result: an exact genetic copy, or clone, of an individual. This was the method used to create Dolly the Sheep.

What does SCNT mean? Let's take it apart:

Somatic cell: A somatic cell is any cell in the body other than sperm and egg, the two types of reproductive cells. Reproductive cells are also called germ cells. In mammals, every somatic cell has two complete sets of chromosomes, whereas the germ cells have only one complete set.

Nuclear: The nucleus is a compartment that holds the cell's DNA. The DNA is divided into packages called chromosomes, and it contains all the information needed to form an organism. It's small differences in our DNA that make each of us unique.

Transfer: Moving an object from one place to another. To make Dolly, researchers isolated a somatic cell from an adult female sheep. Next they removed the nucleus and all of its DNA from an egg cell. Then they transferred the nucleus from the somatic cell to the egg cell. After a couple of chemical tweaks, the egg cell, with its new nucleus, was behaving just like a freshly fertilized egg. It developed into an embryo, which was implanted into a surrogate mother and carried to term. (The transfer step is most often done using an electrical current to fuse the membranes of the egg and the somatic cell.)

The lamb, Dolly, was an exact genetic replica of the adult female sheep that donated the somatic cell. She was the first-ever mammal to be cloned from an adult somatic cell.

Watch these videos of enucleation and nuclear transfer.

Natural fertilization, where egg and sperm join, and SCNT both make the same thing: a dividing ball of cells, called an embryo. So what exactly is the difference between the two?

An embryo's cells all have two complete sets of chromosomes. The difference between fertilization and SCNT lies in where those two sets come from.

In fertilization, the sperm and egg have one set of chromosomes each. When the sperm and egg join, they grow into an embryo with two setsone from the father's sperm and one from the mother's egg.

In SCNT, the egg cell's single set of chromosomes is removed. It is replaced by the nucleus from a somatic cell, which already contains two complete sets of chromosomes. So, in the resulting embryo, both sets of chromosomes come from the somatic cell.

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You may have heard about researchers cloning, or identifying, genes that are responsible for various medical conditions or traits. What's the difference?

When scientists clone an organism, they are making an exact genetic copy of the whole organism, as described above.

When scientists clone a gene, they isolate and make exact copies of just one of an organism's genes. Cloning a gene usually involves copying the DNA sequence of that gene into a smaller, more easily manipulated piece of DNA, such as a plasmid. This process makes it easier to study the function of the individual gene in the laboratory.

Supported by a Science Education Partnership Award (SEPA) Grant No. R25RR016291 from the National Center for Research Resources, a component of the NIH. The contents provided here are solely the responsibility of the authors and do not necessarily represent the official views of NIH.

APA format: Genetic Science Learning Center (2014, June 22) What is Cloning?. Learn.Genetics. Retrieved June 19, 2016, from http://learn.genetics.utah.edu/content/cloning/whatiscloning/ MLA format: Genetic Science Learning Center. "What is Cloning?." Learn.Genetics 19 June 2016 <http://learn.genetics.utah.edu/content/cloning/whatiscloning/> Chicago format: Genetic Science Learning Center, "What is Cloning?," Learn.Genetics, 22 June 2014, <http://learn.genetics.utah.edu/content/cloning/whatiscloning/> (19 June 2016)

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What is Cloning? - Learn Genetics

Human Cloning. Credit: Art Grafts/The Image Bank/Getty Images

Updated February 12, 2016.

Cloning is the process of creating genetically identical copies of biological matter. This may include genes, cells, tissues or entire organisms.

Some organisms generate clones naturally through asexual reproduction. Plants, algae, fungi and protozoa produce spores that develop into new individuals that are genetically identical to the parent organism. Bacteria are capable of creating clones through a type of reproduction called binary fission.

In binary fission, the bacterial DNA is replicated and the original cell is divided into two identical cells.

Natural cloning also occurs in animal organisms during processes such as budding (offspring grows out of the body of the parent), fragmentation (the body of the parent breaks into distinct pieces, each of which can produce an offspring), and parthenogenesis.

In humans and other mammals, the formation of identical twins is a type of natural cloning. In this case, two individuals develop from one fertilized egg.

When we speak of cloning, we typically think of organism cloning, but there are actually three different types of cloning.

Cloning techniques are laboratory processes used to produce offspring that are genetically identical to the donor parent. Clones of adult animals are created by a process called somatic cell nuclear transfer. In this process, the nucleus from a somatic cell is removed and placed into an egg cell that has had its nucleus removed.

A somatic cell is any type of body cell other than a sex cell.

What are the risks of cloning? One of the main concerns as it relates to human cloning is that the current processes used in animal cloning are only successful a very small percentage of the time. Another concern is that the cloned animals that do survive tend to have various health problems and shorter life spans. Scientist have not yet figured out why these problems occur and there is no reason to think that these same problems wouldn't happen in human cloning.

Scientists have been successful in cloning a number of different animals. Some of these animals include sheep, goats, and mice.

How do you spell breakthrough? D-O-L-L-Y Scientists have succeeded in cloning an adult mammal. And Dolly doesn't have a daddy!

First Dolly and Now Millie Scientists have successfully produced cloned transgenic goats.

Cloning Clones Researchers have developed a way to create multi-generations of identical mice.

Cloned Animals View pictures of cloned animals from Guardian Unlimited.

Should humans be cloned? Should human cloning be banned? A major objection to human cloning is that cloned embryos are used to produce embryonic stem cells and the cloned embryos are ultimately destroyed. The same objections are raised with regard to stem cell therapy research that uses embryonic stem cells from non-cloned sources. Changing developments in stem cell research however, could help ease concerns over stem cell use. Scientists have developed new techniques for generating embryonic-like stem cells. These cells could potentially eliminate the need for human embryonic stem cells in therapeutic research. Other ethical concerns about cloning involve the fact that the current process has a very high failure rate. According to the Genetic Science Learning Center, the cloning process only has a success rate of between 0.1 to 3 percent in animals.

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Cloning - Types, Technique, Animals and More

Cloning is the asexual production of an exact copy of an original. So for example, one could use cloning to produce the exact copy of a single cell. The cell copy would be identical to the first cell and would have the same exact DNA sequence. In many cases, cloning has been used to reproduce type specific cells. In some instances, cloning of an individual organism, like the sheep, Dolly, has been possible.

Unlike reproduction that involves two parents, such as a male and female plants, cloning has a single parent. This is often used in reproducing certain plants. Certain plants have undergone cloning processes for thousands of years, but they do not play a part in the ethical debates that surround cloning of animals, and most particularly humans.

For example, reproductive cloning of animals was first attempted in the 1950s. Most identify the sheep Dolly, cloned in 1996. Dollys parent had DNA transferred into an egg that had its nucleus removed. This is called a somatic cell nuclear transfer. The cell was then treated with chemicals and stimulated to grow so than an almost exact replicate of the cloned sheep was born.

In actuality, Dolly was not a precise clone of her parent. She shared the same DNA, but some of the genetic materials of the donor cell also became part of Dollys parentage. This is only .01% of Dollys DNA, but it does make a negligible difference.

The cloning resulting in Dolly was not exactly simple. In fact it took 277 donor eggs, and the production of 29 embryos before a live birth was achieved. Calf cloning experiments with somatic cell nuclear transfer have prospered less than 1% of the time.

However, the idea of cloning humans still remains. While many people feel that cloning human tissue, as for organs for transplant might be valuable, many others feel that cloning a whole human is unethical. Some scientists without religious affiliation also believe that ethical issues that might be engendered in prolonging life through cloned tissues need further scrutiny.

From a moral standpoint, much has to do with how some reproductive clones are made. Many believe that an embryo, even when simply fertilized sperm and egg is a human and thus should not be destroyed. Experimentation of embryos to produce clones often results in embryo death. Further some feel that cloned embryos might be used specifically to harvest body parts and then killed.

Some further feel that the harvesting of stem cells from an embryo is also wrong, or that creating embryos for the purpose of harvesting stem cells is unethical. Others argue that stem cell research may point the way toward curing diseases for which there is currently no cure. It should be noted, however, that fewer people object to the idea of cloning a body part, than cloning a human.

Others are concerned about the cloning of extinct or endangered animals. In fact Michael Crichtons novel Jurassic Park dealt with this theme extensively. Especially since actual dinosaur DNA has been found recently, in enough abundance to clone, some scientists are concerned about the environmental impact that could result from reproducing a long dead species.

In some countries, stem cell research has been halted, when it involves cloning human embryos. Other scientists investigate the possibility of finding stem cells elsewhere, as in the umbilical cord blood of newborns. It is suspected that some countries may be attempting to clone a whole human, but have not yet achieved this.

Though cloning is much in the news, it is still an imperfect science with more failures than successes at present. This suggests that scientists may not fully understand all the mechanisms involved in creating an exact copy of another organism. With further research, such mechanisms may be understood and clear the way toward making clones. Yet, doing so is likely to result in continued controversy.

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What is Cloning? (with pictures) - wiseGEEK

CLONING Websites *Articles

a. Websiteswww.newscientist.com/nsplus/insight/clone/clone.html A special report from New Scientist that's supposedly "everything you always wanted to know" Includes introduction, article index, FAQ, web sightings, bioethics, and news. Has links to New Scientist articles from March 1997-November 1999. The web sightings list some of the better sites on cloning and a couple of scifi things.

http://www.phrma.org/genomics/cloning/ Includes: General Information & News Ethical and Legal Issues Government Resources Research Institutions Advisory Committees & Studies Scientific Organizations Books on this topic Comments Stem Cell Research US State Cloning Legislation

http://www.humancloning.org/ The "official site" in support of human cloning

afgen.com/cloning.html Collection of articles on Bill Clinton's stance on human cloning, cloned monkeys, legal battles, and theological questions.

library.thinkquest.org/19037/clone_links.html Thorough collection of links about cloning and related ideas including the facts, the future, diagrams, ethics, transgenics.

gaytoday.badpuppy.com/cloning.htm Gay Today's series on cloning. Including "Human Cloning: a Promising Cornucopia" and "Staying youthful-Curing AIDS-Human Cloning" and "First Cloning Rights Group Led by Gay Pioneer"

http://www.pathfinder.com/TIME/cloning/home.html Time Magazine's special on cloning. Excellent graphics, simply stated, but well covered.

http://www.sciam.com/1998/1298issue/1298wilmut.html A Scientific American article by Ian Wilmut. Also has other links and suggested further reading

http://www.ri.bbsrc.ac.uk/library/research/cloning/ The official site of the Roslin Institute.

http://www.teleport.com/~samc/clone/ Welcome to the clone age! A very thorough site with lots of links. Including about the recent announcement of a cloned monkey.

http://www.purefood.org/patlink.html CLONING AND PATENTS, Xenotransplantation: News, Articles and Links. Mostly newspaper articles about cloning and genetic engineering.

dspace.dial.pipex.com/srtscot/cloning.shtml The Church of Scotland's page on the ethics of cloning. Covers both human and animal cloning. There are also pages on gene therapy and genetic engineering and human genetics and patents and environment, etc.

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b. Articles

Kluger, Jeffrey. (1999). "Goodbye Dolly." Time. 153(22): 70. Abstract: More than 2 years have passed since the announcement of the successful cloning of a sheep known as Dolly. Scientists have anxiously awaited signs of aging in Dolly to determine if theories are correct that clones may grow old sooner due to the age of the parent cells from which they were cloned. Recent reports indicate that some clones may indeed age faster and, therefore, may have a shorter life span than a normal newborn. This aging appears to involve telomeres, bands at the ends of chromosomes. Telomeres can be said to cap the chromosome strand like the plastic sleeves at the ends of shoelaces. As animals age, the telomeres become shorter. This shortening causes chromosomes to fray and therganism itself to become frail. Researchers have studied the telomeres of Dolly and other cloned sheep and have found that the telomeres are shorter than those of normal sheep of the same age. They reported that Dolly had the shortest telomeres of all. Dolly had been cloned from a 6-year-old sheep, while the others had been cloned from embryos. Age of the donor cell probably plays a role in the shorter telomeres; however, researchers have discovered that the time the clone spends in the test tube before transfer to the womb can also affect the telomeres' length. Cells normally go through 150 divisions in their lifetimes. Scientists note that cells in test tube culture can go through as many as 20 divisions, which is considered to be a significant percentage. The cloned sheep are not expected to meet their demise because of frayed telomeres, but rather from natural causes. However, if the much-longer-lived humans are ever cloned, rapid aging could be a great concern.

Fischman, Josh. (1999). "How to Build a Body Part." Time. 153: 54, 55. Abstract: The discovery of stem cells, precursors to tissue and organ development, and other advancements in cellular biology have prompted 70 lawmakers to sign a letter petitioning the federal government to ban research into the growing of extra body organs for transplanting. By making use of ordinary cells, however, scientists have circumvented the controversy over using aborted fetuses and unwanted embryos for organ development. The technology of tissue engineering has enabled scientists to help patients across the U.S. A skin patch for healing sores and skin ulcers was the first engineered organ approved by the the U.S. Food and Drug Administration. Researchers have discovered how to use polymers to shape molds into which cells can grow and take shape; at this point the molds then dissolve. According to Francois Auger, an infectious-disease specialist and maker of artificial blood vessels at Laval University in Quebec City, Canada, cells will do the prescribed work if they are treated properly. Proper treatment of bone cells by anethesiologist Charles Vacanti, who is also director of the Center for Tissue Engineering at the University of Massachusetts Medical Center in Worcester, enables him to grow bone tissue inside the voids of coral shaped to specifications. Other scientists have used shaped forms of polymer to mold cell growth into the shapes of fingers. Vacanti's brother Joseph has used polymer and sheep-muscle to create blood vessels, which then are attached to a sheep's pulmonary artery. The muscle cells are then exercised and gain strength. Anthony Atala, a surgeon at Boston's Children's Hospital, has used muscle cells from the outside of dog bladders and lining cells to grow tissue to cover and line the sides of a polymer sphere and successfully transplanted the artificial bladder into a dog's urinary system. Although using the patient's cells overcomes problems with rejection, the organ growth rates require as much as several weeks. Michael Sefton, who runs the tissue-engineering center at the University of Toronto, has conceived a ready-made heart that could be grown with genetically engineered cells that would block the signals that evoke immune responses of the host.

Healy, Bernadine. (1999). "Ian Wilmut." Time. 153(12): 116. Abstract: British embryologist Ian Wilmut set out to improve the productivity of farm animals and in doing so, he successfully cloned the sheep known as Dolly. Dolly was reproduced from a single mammary cell from an adult ewe in 1997. This line of research had been abandoned by other major scientific research centers. Wilmut believes that any experimentation with humans should be kept to the level of cells and proteins and believes it is ethically unacceptable to use his technique to clone a human. It was, however, this aspect of his work that attracted the public's attention. Physicist and self-trained researcher Richard Sneed soon proclaimed his intentions of cloning a human, and although few scientists found him credible, this was frightening to many people. Potentially, cloning could play a variety of roles in medicine: basic research, new therapies, infertility solutions, even the cloning of a dying loved one. What is not yet clear is whether clones will die young because of their older DNA or whether they will suffer environmental mutations acquired during the life of their adult parent. Dolly and the strangeness of her background seem remote to
many people and irrelevant to everyday life, but cloning shakes ethical foundations, social norms, and religious beliefs. It raises questions such as what the role of clones in society may be; whether clones are an asexual variant on incest; whether they could become human slaves or organ donors; who their parents are; who their family is, and whether they are made in God's image or man's. It is difficult to discuss cloning in a world where there are widely diverging ethical values and where it often seems that anything is permitted. Israel, Australia, China and most European countries have already prohibited cloning, but the U.S. has not. The question remains whether cloning will sneak up on society so that one day a human infant may be produced in secret. Ian Wilmut, the father of cloning, is passionate about honoring the individuality of the child and believes that human cloning should be banned.

Stone, Richard. (1999). "Cloning the Woolly Mammoth." Discover. 20: 56-63. Abstract: Japanese biologists are leading an attempt to find remnants of a woolly mammoth that may be preserved well enough to supply modern technology with viable sperm or oocytes that could be used in a selective breeding program. Woolly mammoths were most successful during the Pleistocene Epoch from 1.8 million years ago up to the end of the last ice age about 11,000 years ago. The last ones died out about 3,800 years ago. A few proteins and fragmented genes have been preserved well enough in the Siberian permafrost for scientists to recover and compare them with those of modern elephants. Kazufumi Goto, at Kagoshima University in Japan, believes that the resurrection of the mammoth merely requires well-preserved tissue. Goto experimented with bull semen and cow eggs and found that a sperm subjected to repeated freezing and thawing was essentially dead but still able to promote cell cleavage in an egg. Goto began a partnership with Akira Iritani, chairman of the department of genetic engineering at Kinki University in Japan. The researchers prepared for cloning DNA from a woolly mammoth, if suitable material could be found. The researchers set out for Duvannyi Yar, a renowned mammoth site in Russia that contains about 100 mammoth skeletons per square kilometer. Despite a few unsuccessful attempts at uncovering frozen sperm, the Japanese researchers plan to return in the summer of 1999 to known sites of mammoth remnants. Kinki University is also offering 1 million yen ($9,000) for mammoth tissue that is preserved sufficiently for tissue-cloning experiments, according to Iritani. A successful cloning experiment could mean that a woolly mammoth would be added to Pleistocene Park, a 160-square-kilometer preserve near Duvannyi Yar where 32 Yakutian horses, moose, reindeer, and American bison were recently placed.

Cohen, Philip. (1999). "Grow-Your-Own Organs: Adults May Have All the Cells Needed to Regenerate Their Own Tissues." New Scientist. 161(2171) January 30, 1999, Abstract: Using a patient's own tissue to grow replacement organs could be easier than anyone imagined, judging by the ease with which scientists have turned adult brain cells into blood. An international team says that simply injecting the brain's neural stem cells (NSCs) into the bone marrow of mice is enough to promote this metamorphosis. If the same is true in humans, the technique could lead to new sources of perfectly matched transplanted tissue--without the controversial use of human embryonic stem (ES) cells, which are taken from aborted fetuses or discarded in vitro fertilization embryos. Until two years ago, the process of specialization, in which ES cells change to form individual tissues, was considered irreversible. The creators of the cloned sheep Dolly showed that the development potential of an adult cell could be recovered. Angelo Vescovi of the National Neurological Institute in Milan, Italy, and his team suspected that some reprogramming might happen without cellular surgery. Vescovi's team injected NSCs from adult mice into the bone marrow of mice that had been irradiated to cripple the cells that form blood, hoping that this new environment might trigger reprogramming. After 5 months, the recipients developed new blood cells. Genetic analysis confirmed that many of these cells were direct descendants of the NSCs. Vescovi's latest results suggest that the new blood cells are functional, since the irradiated mice that received the NSC transplant lived longer than the irradiated mice that received no transplanted cells. Vescovi believes that it may be possible to use stem cells from other tissues such as skin as the source of new tissue. These cells would be easier to obtain than the brain stem cells used in his work so far.

Watts, Jonathan and Kelly Morris. (1999)."Human Cloning Trial Met with Outrage and Scepticism." The Lancet. 353(9146): 43. Abstract: Researchers at a Korean university infertility clinic announced recently that they had fused an adult cell with an enucleated egg to create an embryo that divided twice to reach the four-cell stage. The researchers then terminated the experiment to avoid flouting ethical guidelines, but claim that the next step would have been to transfer the embryo to a uterus. The researchers used the Honolulu technique, in which a somatic-cell nucleus is inserted into an enucleated egg, followed by ovification of the egg. This technique is a modification of the one used to clone Dolly the sheep, the first vertebrate cloned from an adult cell. The Korean researchers' claims were challenged by scientists around the world. Some noted that the unpublished work of the Korean team is not part of a major cloning project. A Japanese researcher who cloned twin calves said he did not believe the report. A scientist at the Roslin Institute in Scotland where Dolly was cloned states that taking a putative embryo to the four-cell stage is not that important, because a human embryo is preprogrammed to divide to at least the eight-cell stage. He explained that the 100,000 genes in the somatic cell nucleus just be activated rapidly and perform perfectly for 9 months to produce a live healthy clone. The low success rate in animal cloning suggests that a cloned human embryo would likely be stillborn or die after birth. He stressed that nuclear transfer is not just a variation on in-vitro fertilization. In somatic-cell cloning there is also the potential for inheritance of somatic-cell mutations from the donor, since nuclear transfer bypasses mechanisms that correct DNA errors in germ cells. There is also a possibility that DNA in a cloned animal may behave like that of an animal with the combined ages of donor and offspring, possibly shortening the clone's life. The concerns expressed by scientists add to the serious ethical reservations expressed around the world. In Korea, protesters demonstrated outside the university where the cloning experiments took place. Korean newspapers expressed a mixture of dismay and pride. There was a general agreement that Korea needs laws to curb cloning research.

Wilmut, Ian. (1998). "Cloning for Medicine." Scientific American. 279: 58-63. Abstract: Innovations in cloning techniques have opened up a world of possibilities for biomedical researchers. It may soon be possible to clone genetically altered animals as organ donors for humans, so that they will not initiate rejection in the recipient. Animals may also be bred to produce cells used for replacing damaged human cells in such diseases as Parkinson's, diabetes, and muscular dystrophy. Universal stem cells, or cells that are in very early states of development and may be genetically influenced to develop into certain tissues, could be another outcome o
f cloning technology. Although ethical questions would be raised, it may also be possible to raise animals affected with human diseases such as cystic fibrosis for research purposes. Herds of cattle may be cloned that will not be susceptible to bovine spongiform encephalitis, or mad cow disease. Early cloning techniques required scientists to genetically copy cells isolated from early-stage embryos. This process was tedious and impractical for widespread use. In 1995 lambs born at the Roslin Institute in Scotland were the successful offspring of a process that introduced genetic material into cultured embryo cells. Because cultured cells are relatively easy to work with, this technique was a breakthrough in practical cloning. The birth of the sheep Dolly in 1997 was another milestone in cloning techniques, because the cultured cells were taken from a mature ewe rather than an embryo. The process of transferring genetic material to cultured cells is repeatable, but limited in success; only 1-2% of such embryos survive. Transgenic, or genetically modified, animals are produced by injecting a constructed DNA sequence with a desired trait into fertilized eggs. Instead of injecting DNA into an egg, it has been discovered that eggs can be chemically induced to take up a DNA construct, making the process more practical and efficient. Polly, a transgenic sheep born in 1997, carries the gene for human factor IX, a blood-clotting protein, which is expressed in her milk. Transgenic animals have the potential to produce substances that may control or cure many human diseases.

Cohen, Philip. (1998/1999). "Cloning by Numbers." New Scientist. 160(2165/6/7): 28-29 Abstract: The second group to clone an adult animal was a team led by Ryuzo Yanagimachi at the University of Hawaii, Honolulu. Yanagimachi's team produced a clone named Cumulina on October 3, 1997. Since then the group has produced some 80 cloned mice, giving further credence to the work by the Scottish team that produced the first adult animal clone, a sheep named Dolly. Media groups did not predict that Yanagimachi's lab would be the next to produce a clone because the lab initially focused on mouse vitro fertilization, not cloning. Cloning a mouse is extremely difficult, given the small window of opportunity for gene reprogramming. A post-doctorate student named Teruhito Wakayama explored mice cloning as a personal project. Wakayama used cumulus cells, cells present on the egg surface, as donor cells. He removed the cell nucleus and injected the nucleus into an egg cell with its own genetic material removed to produce a living embryo. When Yanagimachi saw this initial success, the entire lab collaborated to produce a cloned mouse a couples of month later. It turns out both the novel technique of injecting a nucleus into an egg and the choice of cumulus cells, of which only some 2% produce clones, were what was needed for successful mice cloning. Since mice reproduce rapidly, the clones are useful tools in discovering more about the aging process in clones, the reasons for cloning success or failure, and the revitalization of dormant genes. This second attempt at adult animal cloning has been followed by the cloning of adult cows by a group in Japan and by a group in New Zealand.

Gearhart, John. (1998). "New Potential for Human Embryonic Stem Cells." Science. 282(5391): 1061-1063. Abstract: Stem cells give rise to all of the different tissue types found in animals. Because these cells, which are present in the early stages of embryo development, are self-renewing, a cultured source of human stem cells able to differentiate into a variety of tissue types would be invaluable in basic medical research and in transplantation therapies. Now researchers at the University of Wisconsin at Madison and the Rambam Medical Center in Haifa, Israel, have succeeded in growing human embryonic stem (ES) cells in culture. These cells were derived from two embryonic tissues: inner cell masses of blastocysts and primordial germ cells. The ES cell lines were continuously cultured over a 5-6 month period and expressed the high levels of telomerase activity typical of cells with a high replicative lifespan. Four cell lines tested produced termatomas (a type of tumor) when grown in immunocompromised mice. In these tumors, researchers detected differentiated cells derived from all three embryonic germ layers: ectoderm; mesoderm; and definitive endoderm. The potential use of human ES cells is far-reaching. ES cells could prove important to in vitro studies of normal human embryogenesis, abnormal development, human gene searches, drug and teratogen testing, and as a renewable source of cells for tissue transplantation, and cell, replacement, and gene therapies. Likely targets for tissue transplantation therapy include neurodegenerative disorders, diabetes, spinal cord injury, and hematopoietic repopulation. However, because human embryos are involved in stem cell research, advances in this area are likely to spark public debate--a debate likely to center around the source of the cells, the potential for human cloning, and concerns about germ line modification.

Kaye, Howard L. (1998). "Anxiety and Genetic Manipulation: A Sociological View." Perspectives in Biology and Medicine. 41: 483-490. Abstract: While the announcement of the successful cloning of a sheep caused widespread panic and distrust, little has been done to understand and respect the nature of these fears. The public concern has been treated as an emotional response based in ignorance and superstition. Some scientists say that cloning offers no greater threat to human autonomy than does twinning, and no greater threat to the family than does artificial insemination with donor semen, in vitro fertilization, or surrogacy, and that identical genes do not make identical people. Those espousing this view believe that alleviating public anxieties requires better science education, not a permanent ban on cloning. The National Bioethics Association agrees, saying that much of the public's fear is rooted in science fiction and gross misunderstandings of human biology and psychology. Many scientists think that the public's moral intuitions are not solid enough to impede scientific progress and that they will embrace the technology when the first successful human clonings are achieved. Sociologists disagree. They say that the almost universal fear that cloning is a threat to the dignity and sanctity of human life should not be dismissed lightly. When it comes to taking a moral stand on unresolved issues, sociology can play a vital role. It can best serve moral life by helping people see clearly the ultimate meaning of their actions. It can help the public anticipate the means that might be necessary to achieve a particular end. It can confront them with consequences that they might otherwise not foresee by helping them understand the social and cultural contexts in which particular courses of action would be followed. Sociology can show the necessity of choice from among desirable ends and compel people to reexamine philosophical arguments and utopian aspirations in the light of lived human experience carefully observed in all its dimensions. In these ways it can help people make moral judgments on subjects such as ethics, transplantation, and cloning.

Pennisi, Elizabeth. (1998). "Cloned Mice Provide Company for Dolly."Science. 281(5376): 495-496. Abstract: Researchers at John A. Burns School of Medicine at the University of Hawaii in Honolulu have succeeded in replicating the cloning of an animal from adult cells-- the same process that produced the cloned sheep "Dolly" and made international headlines in 1997. The Hawaii research team repo
rts the cloning of 50 mice so far. Other researchers who have analyzed Dolly's DNA have confirmed that she is indeed a clone of the ewe whose cellular material was used in the experiment. In the Hawaiian cloning experiment, researchers used the same basic technique as the Scottish team that produced Dolly. Nuclei from adult cells were transferred into eggs whose own nuclei had been removed. But while the Scottish team triggered the fusing of the adult cells with the eggs by applying an electrical pulse, the Hawaiian team used a very fine needle to take up the donor cell nucleus and inject it into an enucleated egg. The Hawaiian team also differed from the Scottish team in the method used to trigger development of the eggs. While Dolly's egg was jolted to development using an electrical pulse, the Hawaiian team put the eggs into a culture medium containing strontium, which stimulates the release of calcium from the internal stores, triggering the development of the fertilized eggs. This strategy proved most effective with cumulus cells, which surround an egg as it matures. The resulting cloned mice appear normal. The researchers have cloned some clones and mated others; all progeny seem normal and healthy.

Lemonick, Michael D. (1998). "Dolly, You're History." Time. 152: 64-65. Abstract: Reproductive biologists have concluded, following over a year's research, that the famous cloned sheep Dolly is indeed, a bona fide clone. In her wake has come a veritable population boom of cloned mice, making what recently seemed a miraculous achievement now appear to be a routine procedure. The primary difference between a cloned animal and one normally conceived is that the clone is created from adult, differentiated cells, while normally conceived animals are derived initially from fetal, undifferentiated cells. A few years back, Japanese postdoctoral student Teruhiko Wakayama, who had studied cloning as a hobby at the University of Hawaii, began to work seriously on attempting to clone mice during his spare time. Although mice had long been considered all but impossible to clone because of the nature of their egg cells and the rapid development of their embryos, Wakayama overcame these problems. Just a few months after Dolly was born, Wakayama succeeded in cloning the cumulus cells that envelope the egg in the ovary. Unlike Wilmut, Wakayama did not use electric shocks to trigger the merging of a host egg with a donor cell. Instead, he injected just the adult nucleus into a nucleus-free host and let the hybrid cell "rest" for several hours before stimulating its division. An astonishing 3% of Wakayama's clones survived, all of them normal in every way. Their DNA proved so robust that they themselves could be cloned and their clones cloned. Wakayama's success has taken the possibility of the routine cloning of larger animals--including humans--a step closer to reality. While scientists point out the potential advantages, such as the mass production of research animals bioengineered to provide human-compatible transplant organs, ethicists point out that there are many problems inherent in human cloning.

Cohen, Philip. (1998)."Clone Alone." New Scientist. 158(2133): 32-35. Abstract: Soon after Ian Wilmut announced in 1997 that he had produced a clone of a sheep, whom he named Dolly, some skeptics were not convinced. The research Wilmut and his group conducted at the Roslin Institute in Scotland is an amazing discovery, given the recent unsuccessful history of cloning adult animals. John Gurdon first attempted cloning frogs in the 1960s and 1970s. He had success with tadpole cells, but failed whenever he tried to use an adult frog cell as the donor cell. Cloning seemed to work as long as cells were not specialized, as is the case with an adult cell. Then Dolly came along. Researchers did not expect success so they were not concerned that their donor was dead with no trace of extra donor tissue. The cloning of an adult animal has not been repeated. This is one among many criticisms of the work of Wilmut. Some feel that the udder cells used to produce Dolly were not tested against adult cells. Norton Zinder and Vittorio Sgaramella wrote of their criticism of the Dolly experiment. First, they say that because Wilmut and his group never compared Dolly's genes with the original adult sheep's, they cannot say for certain that Dolly is a clone. Dolly has been shown only to be related to the culture line of cells that the donor genes originated from. Furthermore, Wilmut's group compared only four regions of DNA to prove their connection between Dolly and the original cultured sheep cells. Zinder and Sgaramella also warn that since the original adult donating Dolly's genes was pregnant, it could mean that Dolly's cells originated from fetal cells. To counter their critics, Wilmut and his group will conduct more advanced analyses of Dolly. First, independent laboratories will carry out a more extensive analysis of Dolly's DNA with udder tissue to determine the probability of a random match. Second, collaborators have found no evidence that fetal cells are present in the blood of pregnant ewes. Third, an independent lab will measure the length of chromosome ends, which will give an indication if Dolly has chromosomes similar to a 6-year-old sheep. The goal of Wilmut's team is to prove that Dolly is indeed an adult clone until they are able to repeat the Dolly experiment.

Nash, J. Madeleine. (1998). "The Case for Cloning." Time. 151: 81. Abstract: The benefits and risks associated with human cloning should be thoroughly evaluated before prohibitive legislation is enacted. However, fears that access to cloning will be easy and widespread have caused many legislators to hastily pass general bans against human cloning. In fact, the Clinton administration supports a proposal with a 5-year moratorium. In addition, House majority leader Dick Armey is backing a bill for permanently banning human cloning, while at least 18 states are considering regulations of their own. The reality that no legislation is sometimes better than bad legislation should temper this debate. California's poorly written legislation temporarily bans human cloning, as well as a promising new infertility treatment. Cloning can have important medical implications. Biologists can parlay the technique used to produce Dolly the sheep solely for medical purposes. Biologists can extract healthy cells from a patient and create embryonic clones. The infusion of growth factors will ensure that the clone does not develop into a fetus, but into specialized cells and tissue for treatment purposes. For instance, cloned cells could provide a graft of new skin for a burn patient and a bone marrow infusion for a leukemia patient. The rejection danger is eliminated, as well as the need for immunosuppressive drugs. The dangers that exist in cloning advances are not in their identical clones that many fear will be churned out, but in the application for genetic engineering to humans. Initially, parents will want genetic diseases such as Tay-Sachs to be eliminated. Then they may want familial predispositions to be eliminated. The ultimate danger will be the desire to enhance normal genetic traits. The issues to be dealt with are which risks and which potential benefits may be withheld from our society due to panic driven decisions.

Morell, Virginia. (1998). "A Clone of One's Own." Discover. 19: 82-89. Abstract: The birth of the now-renowned sheep Dolly, cloned from an adult cell, has opened up a maelstrom of public controversy and generated endless speculation by scientists, philosophers, doctors, and politicians. It has led to a media circus centered around eccentrics such as a Chicago ph
ysicist-turned-biologist Richard Seed, who wants to start his own human cloning business, and French chemist Brigitte Boisselier, who claims aliens had told her all about cloning years ago. On the purely practical side, cloning may eventually offer a way to provide an infertile or homosexual couple with a means to produce a biological child. Researchers say that although such a child may closely resemble their parent in many ways, the experiential differences from the womb on will ensure that such a child is completely unique. However, as most researchers are quick to point out, being able to safely clone humans--if indeed it ever becomes a viable possibility--is still a long way off. Some geneticists think that damage from aging DNA may be passed on to a cloned infant, and long-term studies of cloned mammals will be the only way to determine if this is so. Researcher Don Wolf of the Oregon Regional Primate Research Center has been working to clone rhesus monkeys as a way to create a supply of genetically controlled animals for medical research. Wolf observes that the cloning process is highly involved and far from certain in its results. When Dolly was created, for example, the adult cells from a sheep's udder were placed in a growth serum and "starved" for 5 days to render them inactive. These cells were then fused with 277 different eggs. Of these 277 efforts, 276 failed. Only one--which became Dolly--was successful. Researchers still do not know which cell from the udder worked or why, nor if the serum starvation method will work on other species. Many scientists consider that it would be highly unethical at this stage to try cloning in humans. Nonetheless, cloning is likely being perfected by someone somewhere. And once that happens, it is only a matter of time before the first human clones appear.

Wills, Christopher. (1998). "A Sheep in Clone's Clothing?" Discover. 18: 22-23. Abstract: Since February 1997 when Dolly, the world's first successful clone of an adult mammal (a Dorset sheep), took the world by storm, debates over both the practicality and ethics of cloning have been ongoing. Previous attempts at cloning from adult animal cells failed because the cells were too metabolically active, in the wrong stage of the cell cycle, or had the wrong set of genes turned on. Ian Wilmut of Edinburg's Roslin Institute, who cloned Dolly, compensated for these problems by starving the cells he used for several days before fusing them with enucleated eggs. This caused the cells' DNA-copying machinery to cease, by stopping the cell cycle and forcing cells into a suspended metabolic state similar to that of an unfertilized egg. Nonetheless, Dolly was Wilmut's only success in 277 tries.

Since then, ABS Global of Wisconsin has developed a technique that can create cow embryos from the skin, bladder, and udder cells of adult cows. Once these cells were fused with enucleated eggs, and the fused cells had begun to divide, a single cell was extracted and inserted into another enucleated egg. When an embryo began to form, it was implanted in a surrogate mother cow. ABS claims that as of this fall, the pregnancies appeared to be progressing normally. So what happened to Dolly? Researchers are watching the celebrity sheep to see what long-term physiological effects her unusual conception may have on her. Because she began life with a nucleus from an adult cell, it is possible she may prematurely age. On the other hand, the milieu of the egg cell may somehow be able to reverse the genetic damage due to aging--an exciting prospect. Meanwhile, Britain has already banned human cloning, and the U.S. is following suit. In June 1997, President Clinton said he feared cloning could lead to misguided and malevolent attempts to select certain traits, even to create certain kinds of children, making our children objects rather than cherished individuals. One of the main fears of opponents is that cloning represents total loss of individuality. Researchers argue that even identical twins are not really identical, because there is far more to development than genetics. A clone and its parent would not develop in the same mother, nor in the same uterus or egg. Although they will share nuclear DNA, clones will actually have less in common developmentally than twins. Researchers say that at present, the strongest argument against cloning is its likelihood of failure. In previous work with cells from embryos, three out of five lambs died soon after birth and showed developmental abnormalities. Similar consequences with humans would be totally unacceptable.

Pennisi, Elizabeth. (1997). "The Lamb That Roared." Discover. 278(5346): 2038-2039. Abstract: In February 1997, a 7-month-old lamb named Dolly was the first animal cloned from an adult cell. Although animals had been cloned before, creating a sheep from a single cell of a 6-year-old ewe was a major technological feat that many had thought impossible. Dolly's creation began when a team of researchers at the Roslin Institute outside Edinburgh, Scotland, suspected that previous failures in cloning were caused by donor DNA that was in a different stage of cell cycle than the recipient egg cell. The researchers used nuclear transfer to clone sheep from embryonic cells, and in 1996 announced the birth of two cloned lambs. Next, they cloned sheep from fetal fibroblast cells. And in partnership with a local biotechnology company, they attempted what everyone had said was impossible: to clone a sheep from adult cells. To do this, the team used cultured udder cells, taken from a 6-year-old ewe, and then starved them, forcing most of their genes to enter an inactive phase that the researchers hoped would match the cell-cycle stage of the recipient eggs. Once the udder-cell nuclei were transferred into the eggs, still-unknown factors coaxed that inactivated 6-year-old DNA to go back in time, so to speak, and apparently become totipotent once more, directing the eggs to develop into lambs. Out of 277 such eggs, only one produced a healthy living animal: Dolly. No one, not even the Roslin team, has made a second animal from an adult cell. Attention is focused on the handful of labs worldwide working on cloning in livestock. Most are starting with fetal say they too have cloned either sheep or cows from fetal cells, whose DNA can more easily be made totipotent. So far, several firms cells, and one group has cloned monkeys from embryonic cells. Nuclear transfer experiments are underway in other species too, ranging from zebrafish to rabbits. Among basic researchers, the Scottish group's success has inspired new experiments looking at how DNA changes as a cell matures.

Morton, Oliver. (1997). "First Dolly, Now Headless Tadpoles." Science. 278(5339): 798. Abstract: Eight months after it was announced that scientists had successfully cloned an adult sheep by transferring one of its cell nuclei to an egg, Britain's best-selling broadsheet newspaper, the Sunday Times, ran a front-page headline about headless frogs. The researcher who created the tadpoles while studying developmental genes speculated about their practical use, stating that someday, organs grown through nuclear transfer, followed by strict control of developmental pathways, might provide compatible transplant material for people who otherwise could not get organs. Debate over the ethics of creating brainless humans for medical purposes ensued. Ethicists were quoted as saying the whole idea was deplorable, treating lives as means, and not ends. A developmental biologist said that there are no interesting moral problems at all raised by cloning organs: If the donor is never satient to begin with, what could be the harm? The researche
r working on frogs was investigating the ability of homeobox genes to control development along the long axis of the animal. He mentioned his work and its possible long-term applications to a BBC documentary crew preparing a film about Dolly and the age of cloning. Clones as sources of spare parts are one of the constant components of the post-Dolly debate. Whether the technologies that have stirred public fears will ever become reality is difficult to say. PPL Therapeutics--the company that has licensed the technique from the Roslin Institute where Dolly was cloned, to produce transgenic animals--plans to engineer and clone pigs as donors for xenotransplants (transplants between species, e.g., animal to human). Cloning to produce just human organs, not people, might be an alternative, but there is not yet a real understanding of how this might be accomplished.

Wadman, Meredith. (1997). "U.S. Biologists Adopt Cloning Moratorium." Nature. 389(6649): 319. Abstract: The Federation of American Societies for Experimental Biology (FASEB), one of the leading U.S. professional associations of biologists, announced in September 1997 a voluntary 5-year moratorium on the cloning of human beings. FASEB, however, is also seeking to keep open a window allowing research on human embryos that might otherwise fall under a wider ban on cloning- related research. The president of FASEB, which has 14 member societies representing more than 52,000 scientists, said that his association would regard cloning a human being as an "unethical and reprehensible act." The FASEB moratorium defines cloning human beings as the duplication of an existing or previously existing human being by transferring the nucleus of a differentiated, somatic cell into an enucleated human oocyte, and implanting the resulting product for intrauterine gestation and subsequent birth. The text accompanying the moratorium makes a point of contrasting cloning intended for implantation and for in vitro research. In Washington, a bill was amended in July 1997 by the House of Representatives Science committee to ban federal funding for the use of cloning for in vitro research in human embryos as well as for producing human beings. FASEB officials deny that the moratorium is intended to respond to the House Science Committee's vote to outlaw the use of cloning technology for in vitro research on human embryos. By permitting research on human cells in vitro, scientists would be able to better understand how adult nuclei are reprogrammed by cellular cytoplasm, possibly opening avenues to novel ways of repairing and regenerating human tissues, according to the FASEB.

Thompson, Dick. (1997). "To Ban or Not to Ban?" Time. 149(24): 66. Abstract: In response to President Clinton's request, the National Bioethics Advisory Commission issued a report that recommends making the cloning of a human being a criminal offense in the U.S. Before Dolly had been cloned from the mammary cell of an adult ewe, scientists thought that the DNA of a mature mammalian cell was pre- determined to build skin, bones, or soft tissue, but not an entire organism. Scientists are eager to study how a differentiated cell was made to behave like an embryo. While examining the mechanisms by which genes are activated or deactivated, scientists might even find clues to the origins of cancer and diseases such as muscular dystrophy and cystic fibrosis. Although the use of federal funds for research on human embryos has been prohibited, privately owned labs, including in vitro-fertilization clinics, grew through the 1980s. Some of the National Bioethics Advisory Commission members believe that rapid growth in private research will also occur with human cloning. The commission's report, "Cloning Human Beings," strongly recommends continuation of the ban on federally funded human-embryo research, but only requests that the private sector decide for itself not to deploy such research. Future hearings on the matter could beg the question of where to draw the line, much as the pro-life movement has been asking the question of whether life begins at conception. John Cavanough-O'Keefe of the American Life League attacked the commission on grounds that it was leaning toward allowing human-cloning research as long as cloned embryos are not implanted in a womb. Cavanough-O'Keefe finds the decision doubly wrong in creating human embryos and then predetermining their destruction. The commission members recommended that the cloning issue be re- evaluated periodically because of the possibility that society may one day find cloning more acceptable.

"Clinton Seeks to Ban Human Cloning but Not All Experiments." New York Times. June 10, 1997: B10. Abstract: President Clinton said that he wants to ban the cloning of human beings but allow some cloning research while Americans debate the moral implications. He stopped short of banning the cloning of animals and certain human genes for important biomedical research. The President's proposal is based on the bioethics panel's conclusion that it is "morally unacceptable" to create a child through transferring the nucleus of an adult tissue cell and implanting it into a woman's body. Scottish scientists used such a process to create the sheep named Dolly, the first mammal cloned from an adult cell. Before Dolly was born healthy and normal, the effort had failed 277 times. Some of the lambs were born with severe and lethal birth defects. After learning of Dolly in March 1997, President Clinton banned federal spending on cloning research until the ethical and moral issues could be sorted out while urging the private sector to follow suit.

Pennisi, Elizabeth. (1997). "Transgenic Lambs from Cloning Lab." Science. 277(5326): 631. Abstract: Prior to the birth of the lamb named Dolly, cloned from the cells of an adult, three other lambs were cloned from fetal cells. The two institutions responsible for cloning the lambs, the Roslin Institute of Edinburgh, Scotland, and the Scottish Biotechnology company PPL Therapeutics, have combined the fetal-cell procedure with genetic engineering, taking cloning a step further with the possibility of producing domestic animals with designer genomes. On July 4, 1997, the birth of five lambs cloned from fetal cells was announced. Different from Dolly and her cohorts, these animals carry extra genes that researchers introduced into the cells before they were cloned. A human gene was among the extra genes, although the biotechnology firm will not disclose the identity of the gene. This achievement could aid efforts to develop livestock for producing human proteins, such as blood- clotting factors. Fetal skin cells called fibroblasts were introduced to DNA that included both the human transplant gene and the undisclosed gene marker. After eliminating cells that did not express the marker gene, the researchers tested to see which of the remaining cells also took up the human gene. Following the same cloning strategy used to produce Dolly, they removed the nuclei from mature egg cells and used a brief electrical pulse to fuse the enucleated eggs with the engineered fibroblasts, which had been starved of nutrients. The pulse also jump-started the developmental program, with the genetic instructions now coming from the fetal-cell DNA. The eggs were then placed in the ewes to develop. All five of the new lambs carry the marker gene, and one has already proved to have the human gene in her cells. The birth of that lamb shows that the foreign DNA in the fibroblast genome did not disrupt the genetic instructions that guide the lamb's development. The technique should facilitate the development of animals with customized genomes, including those that have had gen
es removed as well as added. The procedure could help in improving prospects for xenotransplantation by removing immunogenic proteins from pigs whose organs would be used for replacing ailing human ones.

Praded, Joni. (1997). "Cloning: The Missing Debate." Animals. 130: 21-23. Abstract: Scottish embryologist Ian Wilmut and his fellow researchers at the Roslin Institute were the first to clone a mammal from adult cells. They extracted an egg from an ewe and replaced the genes of that egg with deoxyribonucleic acid (DNA) from another adult ewe's mammary gland. Contrary to prior scientific belief, an embryo developed. Wilmut inserted the embryo into a third ewe who gave birth 150 days later, in July 1996, to "Dolly," an exact replica of the adult whose mammary gland was tapped. Dolly's creation was first made public in February 1997, causing a public frenzy over the ethics of cloning humans. Soon after came the news that the Oregon Regional Primate Center had produced sibling rhesus monkeys from cloned embryos. In the midst of the debates over human cloning, concerns about the animals involved in or created by cloning experiments were hardly mentioned. Some animal advocates have reservations about creating any genetically altered animal--clone or not. Animals are being created with serious threats to their own health and welfare. While many believe the benefits of research outweigh the cost of animal suffering, a recent CNN poll reported 66% of the U.S. population opposes cloning animals. Some scientists argue that eventually cloning technologies could limit the number of research animals needed. However, the biotechnology revolution has given rise to two brand-new industries that will undoubtedly consume great numbers of animals: one looks to mass-produce animals that can generate pharmaceuticals; the other, animals whose organs can be humanized for use as spare parts. The resolution of this debate will hopefully come from a careful, widespread analysis of the issues at hand, intelligent regulation, and a greater sense of social responsibility among scientists and industry.

Coghlan, Andy. (1997). "Cloning Report Leaves Loophole." New Scientist. June 14, 1997, 154(2086) Abstract: An ethics panel comprised of scientific experts appointed by President Bill Clinton delivered its conclusions to the President in June 1997, stating that human cloning should be banned in the U.S., but laws to control the practice should be flexible enough to allow a rethink in the future. The panel recommendations would allow researchers in the private sector to make cloned human embryos for experimental work, provided they are eventually destroyed rather than being implanted. The National Bioethics Advisory Commission was asked to review the implications of cloning immediately after researchers at the Roslin Institute near Edinburgh, Scotland, announced the creation of Dolly, a lamb cloned from an udder cell from an adult ewe. Clinton introduced a moratorium on government funding for human cloning research, and asked the private sector to observe its own moratorium. The moratoria should be maintained for now, the commission suggests. Clinton launched a bill to ban the creation of children by cloning. The commission was unable to agree whether cloning should be outlawed on moral grounds, but did agree that safety concerns justify a ban on human cloning for the time being. One concern of commission members is that cancer-causing mutations in donor cells from an adult human would be inherited. Cloned children might also suffer from disruption to a phenomenon called imprinting, in which genes are normally activated differently depending on whether they come from the mother or the father. Another worry is that the clones would grow old prematurely. Advances in animal cloning should be reviewed every 3 to 5 years, according to the panel, to take account of medical techniques that might be used safely in humans. Cloning may bring medical advances such as the cloning of specific body tissues to repair injuries. The idea of the creation of human clones merely to serve as organ banks was termed "repugnant" by the panel.

Marwick, Charles. (1997). "Put Human Cloning on Hold, Say Bioethicists." Journal of the American Medical Association. 278: 13-14. Abstract: According to the National Bioethics Commission, human cloning should be put on hold temporarily. President Clinton asked the group in February 1997 to review the legal and ethical issues surrounding the cloning. The president's request was a response to the successful cloning in Scotland of Dolly the sheep. The commission recommends the enactment of federal legislation to prohibit anyone from attempting to create a child through somatic cell nuclear transfer cloning. The report called the procedure morally unacceptable at this time. However, the report continued, any legislation should be temporary and subject to review within a 3- to 5-year period, at which time the technological situations should be reevaluated and the ethical and social issues reviewed. Transferring the nucleus of a somatic cell into an egg and implanting it is the technique used by Ian Wilmut and colleagues that resulted in the sheep Dolly. However, commission members were concerned that human cloning by any technique, not just the one used by the Scottish researchers, was unacceptable. The commission concluded that to create children in this manner is unethical at this time because of the evidence that such techniques would be neither effective nor safe. The report noted that it took 277 tries before the Scottish researchers succeeded in creating Dolly. Even if safety concerns are resolved, significant concerns remain about the negative impact of the use of such a technology on both individuals and society.

Kolata, Gina. "Iconoclastic Genius of Cloning." New York Times. June 3, 1997: B7, B12. Abstract: Dr. Steen Malte Willadsen is a leader in the field of embryology. He started out as a veterinarian in his native country, Denmark, then was a research fellow in England. Recently he was cloning cattle embryos in Texas and western Canada, and today he is a freelance innovator in Florida. Fellow scientists describe Willadsen as a "genius and iconoclast," while some even rumor he was the first to clone an adult animal. Dr. Willadsen denies those rumors, though he was the first to clone an animal from embryo cells. He has even made chimeras animals half sheep and half goat -- and even a sheep/cow combination. Human eggs are the subject of Willadsen's current research where he is again pushing the envelope. At Cambridge in 1973 Willadsen immersed himself in work on farm animal embryology. In his perfection of methods for freezing sheep and cow embryos, wild and daring experiments were not out of the question for Willadsen. He split embryos in two to create twins and later with Carole Fehily (who later became his wife), he created chimeras by mixing cells from embryos of different species. The chimeras were a minor part of his research, with the main focus always animal breeding, a potentially lucrative business. In 1986 Dr. Willadsen published his embryo cloning work on sheep in the journal Nature. Since that time, he has worked for several genetic companies in the United States and Canada. As early as 1982 Willadsen began cutting-edge cloning research using embryos which were developmentally advanced. Rumors of this work led Dr. Ian Wilmut to question the old dogma that cloning differentiated and began his research on cloning from advanced cells. Wilmut cloned the first animal from an adult cell in 1997. Dr. Willadsen's current work is on methods to freeze mouse and human embryos and on rejuvenating human embryos that
have failed to develop. He believes that human cloning will happen in the future if it has not already accidentally occurred in infertility clinics, though he admits the chances are very small.

Coghlan, Andy. (1997). "Will Cloned Cows Rise from the Dead?" New Scientist. March 8, 1997, 153(2072) Abstract: Henrik Callesen and colleagues have been trying to clone cows using donor cells from cows that have been dead for about half an hour. To begin the experiment, adult cells and immature, unfertilized eggs called oocytes are removed from the cows' ovaries. Next, the oocyte is emptied of its DNA. Using electricity, this empty cell is fused with an adult ovary cell and allowed to grow for 1 week. The researchers are still trying to get the cells to reach a pre-embryonic, division stage called a blastocyst. When a blastocyst develops, Callesen will transfer the cloned cell into the womb of a cow where it is expected to develop normally. Alan Trounson and an Australian team are also trying to clone cows. They get their donor either from fetuses or the ovaries of live cows. Like Callesen's team, they have not achieved a pregnancy yet. Trounson believes cloned cows could be used to produce drugs like interferon more cheaply than standard methods. Cloning cows from dead cells has raised public concern that dead humans might be cloned. According to Trounson, cloning dead humans is not being considered by the scientific community. Cloning dead people would be extremely difficult since the DNA must be perfect and cells decompose very quickly after death.

Gordon, Meg. (1997). "Suffering of the Lambs." New Scientist. 154(2079): 16-17. Abstract: Biotechnology companies like PPL Therapeutics in Scotland raise livestock that have been genetically engineered to produce milk with great medicinal value. At PPL, sheep have been manipulated to secrete in their milk a protein called alpha-1-antitrypsin, which helps to treat cystic fibrosis. Genetic engineering for livestock has proven less than efficient, with some animals producing low yields, and some with high yields. If future generations of genetically engineered livestock could be cloned from a current herd's top producer, the technique that recently created Dolly the sheep, pharmaceutical companies involved in such research would see their profits increase markedly. Now that cloning has the potential to turn a rare experimental procedure--the creation of transgenic animals--into a profitable, industrial process, ethicists, geneticists, agriculturalists, and animal welfare activists are warning that the new technology could encourage serious abuses of animal welfare. Current laws on transgenic animals are nonspecific. In the U.S., once an animal has been engineered to produce a protein that is to be tested as a medicine, its welfare is largely regulated by the Food and Drug Administration (FDA) under the same laws that would govern a vat of cells. There are no safeguards in the U.S. to prevent a company from creating large numbers of transgenic animals before the company is certain that the foreign gene will not harm the animal or its offspring. Out of 10,000 eggs injected with foreign DNA, only about three make it to adulthood and produce the desired protein in sufficiently high quantities. The techniques used to create Dolly offer two possible shortcuts. One could create just one transgenic animal by conventional techniques and then clone it ad infinitum to create flocks for drug testing, or because Dolly's genetic material came from cultured cells from adult sheep, the genetic manipulation could be done in these cells. Researchers concede that they have more work to do before cloning and transgenics can be combined. Some academics argue that the laws covering the protection of animals used in these technologies are not comprehensive enough. Some suggest that the only way to ensure the avoidance of abuses may be to have transgenic animals monitored constantly.

Wright, Robert. (1997). "Can Souls Be Xeroxed?: Your Clone Might Be Eerily Like You. Or Perhaps Eerily Like Someone Else." Time. 149(10): 73. Abstract: What would the world be like if human cloning becomes a reality? Most likely people with high self- esteem would be the only ones using it--people who think the world needs more people just like them. The assumption is that psyches get copied along with the genes. However, although some people may be genetically prone to high self-esteem, everyone's self-esteem depends greatly on social feedback. Early in this century an effort at behavioral genetics divided people into classes such as mesomorphs (physically robust and psychologically assertive) and ectomorphs (skinny, nervous, and shy). These generalizations don't necessarily mean that ectomorphs have genes for shyness. It may just mean skinny people tend to get pushed around more and their personality adapts. Another assumption people have is that if they reared their clone they would experience an uncanny empathy with them. The truth is if you tried hard enough you could similarly empathize with people who weren't your clone by relating common experiences. The cause of this clonal empathy wouldn't be that your inner life was exactly like your clone's. It would be seeing that familiar face, reminding you that you and your clone were essentially the same, driven by the same hopes and fears. You may feel you share the same soul because, in a sense, you share the same soul with everyone.

Kahn, Axel. (1997). "Clone Mammals...Clone Man?" Nature. 386(6621): 119. Abstract: In 1997 researchers cloned viable sheep from adult cells. Now, researchers are questioning the possibility of human cloning. There is no reason why humans should behave very differently from other mammals where cloning is possible. The cloning of an adult human could become feasible using the techniques reported. The topic of human cloning has been greatly debated. Scientists question the medical and scientific justification for cloning humans. Previous debates have identified the preparation of immuno-compatible differentiated cells lines for transplantation, as one potential indication. Researchers imagine everyone having their own reserve of therapeutic cells that would increase their chance of being cured of various disease, such as cancer, degenerative disorders, and viral or inflammatory diseases. Applying the technique used in sheep directly to humans would yield a clone of the father and not a shared descendant of both the father and mother. Nevertheless, for a woman the act of carrying a fetus can be as important as being its biological mother. The extraordinary power of such maternal reappropriation of the embryo can be seen from the strong demand for pregnancies in post-menopausal women, and for embryo and oocyte donations to circumvent female sterility. Moreover, if cloning techniques were ever to be used, the mother would be contributing her mitochondrial genome.

Anderson, Ian. (1997). "Will Many Clones Make Light Work." New Scientist. March 15, 1997, 153(2073) Abstract: Scientists working on the cloning of animals are moving toward mass production. Australian scientists have created almost 500 genetically identical embryos, but they must still prove that mass-produced embryos, can result in healthy pregnancies. This technology could be combined with the technique for cloning adult animals pioneered in Scotland. This would make possible the creation of hundreds of copies of an adult animal. The Scottish team succeeded in cloning a single lamb from 277 sheep udder cells. There are several groups around the world currently experimenting with cloning. The Australians are collaborating with a farmer-o
wned cooperative interested in new technologies for animal breeding. They are developing a production process for genetically identical embryos. Embryos are produced and left for four or five days to divide into a ball of cells called a blastocyst. The researchers then separate up to 30 cells and, like the Scottish team, use an electric current to fuse them with the cytoplasm of an unfertilized egg cell that has had its own DNA removed. The resulting genetically identical embryos are grown and separated repeatedly. The egg cells are taken from cow ovaries obtained at slaughter houses. Previously, no group had produced more than 100 embryos from a single blastocyst but the Australians' record is 470. The key factor is thought to be providing sufficient cytoplasm for each embryo. Most of the embryos produced by the Australians have not been implanted in surrogate mothers, but six calves, including one set of twins, have been born using the new technology. These calves did not come from the 470 genetically identical embryos. Researchers are attempting to find a technique for the production of cattle that is more efficient than artificial insemination (AI). AI allows farmers to fertilize many cows with the sperm of a bull with desirable genetic characteristics, but the cows may be of variable genetic quality. The new technique should permit fertilization of an elite cow's eggs with sperm from a prize bull and subsequently produce hundreds of genetically identical calves. A member of the Scottish group said that the combination of this technique with his group's adult cloning technique should have some useful applications. However, he added that the Australian group has yet to show that their mass-produced embryos produce healthy pregnancies and offspring, since cloned embryos often fail to develop.

Marshall, Eliot. (1997). "Mammalian Cloning Debate Heats Up." Science. 275(5307): 1733. Abstract: In response to embryologist Ian Wilmut's cloning of Dolly, a Scottish mountain sheep, the National Bioethics Advisory Commission (NBAC) began hearings on the cloning of humans. President Clinton banned all federally funded research until NBAC provides an opinion expected by the end of May 1997. Although the cloning of humans presents ethical questions, Harold Varmus, director of the National Institutes of Health, is focusing on the technological benefits of cloning. At a press conference, Varmus suggested that the technique might provide insight into how cells of the early embryo regulate gene function. The information could provide keys to enable scientists to activate good genes or deactivate bad genes. Varmus also added that the technique might enable researchers to create custom-designed transgenic animals that can mass produce human proteins, clotting factor, fibrinogen, or tissue for organ transplants. Varmus and Wilmut have asked Congress to wait for the results of the NBAC review before enacting new laws. However, three bills have already been introduced. One bill would prohibit federal funding for any research or project that involves the use of a human somatic cell for the process of producing a human clone. Another bill outlaws the use of a human somatic cell for producing a human cell. And a third bill bans the use of federal spending for research into human cloning.

Stephenson, Joan. (1997). "Threatened Bans on Human Cloning Research Could Hamper Advances." Journal of the American Medical Association. 277(13): 1023-1026. Abstract: The announcement of a cloned sheep from the DNA in a single udder cell of a 6-year-old ewe has ignited a debate on ethical implications of cloning and sparked the imaginations of researchers regarding the scientific implications and potential of cloning. Several countries, including the U.S., have banned the cloning of human beings. There is definitely a need to analyze cloning because of ethical and legal issues related to reproduction, genetic manipulation, and rights to privacy as well as the public's initial suspicion concerning any new technology that may play a role in the area of sexual reproduction. Many researchers feel that a temporary ban on cloning and an analysis by the National Bioethics Advisory Commission would reassure the public and forestall a rush to enact laws that go far beyond banning the cloning of whole individuals. Some researchers are worried that a broadly worded ban would block basic and applied research using cloning techniques on human cells, because this type of research has the potential to answer important questions in cell regulation and could pave the way for therapeutic advances.

Kluger, Jeffrey. (1997). "Will We Follow the Sheep?" Time. 149(10): 66, 70-72. Abstract: Recently Scottish embryologists announced that they had succeeded in cloning a sheep from a single adult cell. Even though this breakthrough took years to accomplish, science seems to have been the easy part. The social and philosophical implications are just beginning. One obvious question is how will the new technology be regulated? President Clinton recently took a step toward answering this and other questions by charging a federal commission with the task of investigating the legal and ethical implications of the new technology and reporting their findings within 90 days. Also, the House subcommittee on basic research will hold a hearing to address the same issues. Of all the reasons for using this new technology, pure ego is the most disturbing. Some argue that cloning is not very different from genetically engineering an embryo to eliminate a genetic disease like cystic fibrosis, or from in vitro fertilization. More palatable than the ego clone to some bioethicists is the medical clone, a baby created to provide transplant material, like bone marrow, for the original. If anything will prevent human cloning from becoming a reality, it is that science may not be able to clear the ethical high bar that would allow basic research to get under way. Even if governments ban cloning outright, it will not be so easy to police what goes on in private or pirate laboratories. Science needs to get its ethical house in order quickly.

Nash, J. Madeleine. (1997). "The Age of Cloning: A Line Has Been Crossed and Reproductive Biology Will Never Be the Same for People or for Sheep." Time. 149(10): 62-65. Abstract: Researchers at the Roslin Institute near Edinburgh, Scotland, have made possible what seemed like a scientific impossibility. From a cell in an adult ewe's mammary gland, embryologist Ian Wilmut and his colleagues created a lamb named Dolly, who is a carbon copy of her mother. She is in essence her mother's identical twin. Now that this biological barrier has been crossed, many exciting possibilities exist, from propagating endangered animal species to producing replacement organs for transplant patients. But the possibility of misuse of this technology exists as well. Cloning mammals by splitting embryos in half is not new, but cloning mammals from cells that are not embryonic is. To create Dolly, the Roslin team took cells from the udder of a Finn Dorset ewe. To stop them from dividing, the researchers starved the cells of nutrients for a week. An unfertilized egg cell was taken from a Scottish Blackface ewe. The nucleus, with its DNA, was sucked out, leaving an empty egg cell containing all the cellular machinery necessary to produce an embryo. The two cells were placed next to each other and an electric pulse caused them to fuse together. A second pulse mimicked the burst of energy at natural fertilization, jump-starting cell division. About one week later, the resulting embryo was implanted in the uterus of another Blackface ewe. After a gestation period, the pregnant Blackfa
ce ewe gave birth to Dolly, who is genetically identical to the original donor. Undoubtedly, this breakthrough has raised more questions than it has answered. So far, there is no talk of cloning humans, but policymakers will need to find ways to prevent abuses without blocking scientific progress.

Cohen, John. (1997). "Can Cloning Help Save Beleaguered Species?" Science. 276(5317): 1329-1330. Abstract: Since the successful cloning of a sheep ("Dolly") in Scotland, conservation biologists are beginning to seriously explore the possibilities--and ramifications-- of cloning endangered species. Since 1975, the San Diego Zoo's Center for Reproduction of Endangered Species (CRES) has been storing fibroblasts frozen in liquid nitrogen from several endangered species. The cells, originally destined for genetic study, could realistically be used one day to clone live animals. Kurt Benirschke, who launched the cell storage program, would like to see as many cells from endangered species around the world saved as possible. CRES geneticist Oliver Ryder believes that mixing genetic material from long-dead animals (through cloned creatures) with that of surviving members of a species could insure otherwise lost genetic diversity within a species. This practice could enable zoos to retain smaller herds while retaining genetic diversity. For animals that don't breed well in captivity, cloning offers a needed resource. Some biologists fear that cloning as a way to preserve species could divert funds and efforts from other vital wildlife conservation efforts such as habitat preservation. Others point out the high rate of failure in assisted breeding efforts even in familiar domestic species (Dolly required 277 attempts) and the exorbitant cost to a branch of research already struggling with limited funding makes cloning undesirable as well as unrealistic. But most agree that cloning may prove to be the only remaining "window of opportunity" for some species on the brink of extinction.

Fackelmann, K. A. (1994). "Embryo Research Panel Ignites Debate." Science News. 146(14): 212. Abstract: A National Institutes of Health (NIH) advisory panel has released its proposed guidelines for federally funded research on very early human embryos. In general, the panel would allow experiments on embryos up to the 4th day after fertilization, a time when the nervous system and various organs start to develop. The U.S. has had a de facto ban on federal funding of any research involving human embryos since 1980. However, in 1993 Congress passed a law that paved the way for federal review and funding of such projects. Currently, embryo research in the U.S. is funded privately. The 19-member panel also recommended federal support for research on "spare" embryos, those that go unused at in vitro fertilization clinics. The panel also approved an experimental technique called preimplantation diagnosis, which involves drawing off one or two cells from a very young embryo in order to diagnose certain genetic diseases, such as cystic fibrosis. The panel okayed the practice of determining the gender of embryos in order to avoid a sex-linked genetic disease, such as hemophilia. The group advised against the sexing of embryos for any other purpose. Another procedure the panel approved was the creation of "parthenotes," or human eggs that have been stimulated with chemicals or an electric shock to divide. These dividing cells are not fertilized with a sperm and are grossly abnormal. However, researchers believe studies of such eggs may lead to a better understanding of the paternal role in fertilization. The panel came out against the transfer of human embryos to the wombs of animals for further development and urged a prohibition on crossing human and animal sex cells. The panel also recommended against providing federal money for twinning, or cloning human embryos, which could result in the birth of identical twins or triplets. Now the report gets passed on to another NIH advisory committee, which will consider the initial panel's recommendations as well as public comments. It will then send its recommendations NIH director Harold Varmus who will make the final decision.

Voelker, Rebecca. (1994). "A Clone by Any Other Name Is Still an Ethical Concern." Journal of the American Medical Association. 271: 331-332. Abstract: Public and private groups were to convene in February 1994 to lay the groundwork for future policy recommendations on how human embryo research should proceed and the types of clinical applications that may be considered appropriate. Much of the current controversy over such research has been fueled by intense media speculation and concerns surrounding laboratory efforts to duplicate polyploid embryos. Federally sponsored research on in vitro fertilization (IVF) has been held in abeyance since 1980 until last year, when Congress and the Clinton administration allowed such research to again receive federal support. Also in February, the National Institutes of Health (NIH) human embryo research panel was scheduled to recommend appropriate directions for government-sponsored research and guidelines for carrying it out. The group was not to consider research on or the ethics of human germ-line gene modification. Two weeks after the NIH has concluded its initial discussions, the private group National Advisory Board on Ethics in Reproduction (NABER) will meet to debate the scientific and ethical questions arising from research on the cloning of polyploid embryos done at George Washington University Medical Center in Washington, DC. Specifically, NABER wants to know more about how the university review board decided to allow the experiment to proceed. Much scientific debate has focused on what a clone really is. Some scientists use a fairly broad definition: A clone is an identical replication, a duplicate copy. Others define cloning as taking the nucleus of a cell from the body of an adult and tranferring it to an unfertilized egg, destroying the genome of the oocyte of the egg, and letting it develop. This process is different from that done at George Washington, which has also been referred to as twinning. The process is also different from nuclear transportation--taking a nucleus from a 50- to 80-cell embryo and transplanting it to an unfertilized egg from which the nuclear material has been removed. Critics of the George Washington research argue that the duplicates produced could not have been identical because, among other factors, the chromosomes in daughter cells are not identical. The university researchers admit that they did not perform a genetic analysis of embryos produced in their laboratory to confirm whether they were identical copies. The researchers say they will not proceed with their research until the ethical debate matures and possibly provides some guidelines. They also note that their research has provided a unique opportunity for ethicists, scientists, physicians, and patients: The procedure can be debated well in advance of being used in a clinical setting.

Fackelmann, K.A. (1993). "Researchers 'Clone' Human Embryos." Science News. 144(18): 276. Abstract: For the first time, scientists have "cloned" human embryos, a step that has raised a host of ethical and scientific issues regarding the brave new world of reproductive research. Although it is not unusual for researchers to clone animal embryos, this marks the first known attempt to split a human embryo into individual cells, a technique more accurately described as "twinning." Twinning could have the practical application of increasing the chances of pregnancy among women who have undergone in vitro fertilization. The scientists, from George Washington Univer
sity in Washington, DC, conducted their experiment with 17 very young, abnormal human embryos which could not be viable. They stripped the embryos of their tough coating called the zona pellucida then separated the individual cells which ranged from two to eight cells per embryo. The 48 resulting cells were coated with artificial shells and allowed to grow. The cells split from a two-cell embryo appeared best able to divide, with some reaching the 32- cell stage of development. These results suggest that this process could be used to create viable embryos if used with normal starting embryos. The question which must be answered now is whether or not the technique should be used.

Miller, S.K. and Gail Vines. (1993). "Human Clones Split Fertility Experts." New Scientist. October 30, 1993, 140(1897) Abstract: American researchers have cloned human embryos in an experiment aimed at adding new options to the armory of the fertility clinic. Researchers from the George Washington University Medical Center performed the experiment on embryos obtained from women undergoing IVF (in vitro fertilization) treatment. These embryos had the fatal defect of having been fertilized by more than one sperm, giving them three or more sets of chromosomes. The researchers split 17 embryos, each containing two to eight cells, then coated the individual cells with a gel-like substance to form an artificial zona pellucida, the protective membrane around an embryo. The most successful clones, which reached the 32-cell stage before dying, developed from embryos which had been split at the two-cell stage. The ultimate goal of the work is to increase the odds of pregnancy in women of low fertility. The IVF current practice is to give women hormones which induce them to produce multiple eggs which are then removed, fertilized externally and then implanted. Cloning would replace the need for hormone treatment. The U.S. has no national policy or agency regulating embryo research, although a long-standing ban on federal funding for such research was lifted by President Clinton when he took office. All parties involved realize the ethical implications of this type of research. If viable cloned embryos were frozen, parents could give birth to a twin at a later date, perhaps to replace a dead child, or to provide bone marrow or other organs for a sick child. Embryo splitting is considered unethical and is illegal in Britain.

Elmer-Dewitt, Philip. (1993). "Cloning: Where Do We Draw the Line?" Time. 142(19): 64-70. Abstract: In a landmark experiment at George Washington University, researchers Robert Stillman and Jerry Hall duplicated a human embryo. As part of a fertility treatment, eggs were removed from a woman and fertilized in a Petri dish. Some of these eggs were fertilized by more than one sperm--an abnormal condition. One such abnormal cell divided in two as the first step in development. The coating was removed with an enzyme, and the two cells were separated. Using a novel technique, artificial zona coatings were added, allowing development to proceed. The cells continued to divide, forming genetically identical embryos. Development stopped after six d, partly because the embryo was abnormal. To Hall and Stillman, human cloning is simply the next step in the logical progression that started with in- vitro fertilization and is driven by a desire to relieve human suffering--in this case, the suffering of infertile couples. But it was the start of the fiercest scientific debate about medical ethics since the birth of the first test-tube baby 15 yr. ago. Many of the uses envisioned for cloning are not particularly farfetched compared with things that are already happening. A few years ago, faced with the news that their daughter was dying of leukemia, the father braved a vasectomy reversal and the mother a pregnancy at 43 to have a child born for the purpose of providing the bone-marrow transplant that saved the older child's life. Husband and wives who have been through in-vitro fertilization with some embryos left over have had to wrestle with the fact that they have a potential human being stored on ice. When the profit motive enters into the equations, ethical considerations tend to be forgotten. And private profit drives the infertility business in the U.S. There are already catalogs that list the characteristics of sperm donors--including one made up of Nobel prizewinners. Most people seem to respond to the idea of human cloning at a fundamental level. In a TIME/CNN poll, 58% said they thought cloning was morally wrong, while 63% said they believed it was against God's will. On an international front, France, Germany and Japan expressed disapproval. More than 25 countries have commissions that set policy on reproductive technology. In October, a report by the Congressional Office of Technology recommended that the government step in. Under President Carter, a presidential commission was established that developed broad policy guidelines in some of the most controversial issues in medicine, such as deciding when brain death has occurred or when it is ethically correct for a doctor to withhold treatment. The commission was disbanded in 1983. It is now likely that some kind of national board will be established during President Clinton's watch.

Nash, J. Madeleine. (1993). "They Clone Cattle, Don't They?" Time. 142(19): 68. Abstract: To see the future of cloning, one could look at the livestock industry, the proving ground for reproductive technology. More than a decade has passed since the first calves, lambs, and piglets were cloned, and yet there are no dairy herds composed of carbon-copy cows, no pigpens filled with identical sows. While copying particular strains of valuable plants such as corn and canola has become an indispensable tool of modern agriculture, cloning farm animals, feasible as it may be, has never become widespread. Even simple embryo splitting, the technique used by the George Washington University researchers on human cells, is too expensive and complicated to take off commercially. But people have tried to turn livestock cloning into a booming branch of agribusiness. Wisconsin -based American Breeders Service, a subsidiary of W.R. Grace & Co., now owns the rights to cattle-cloning technology developed by Granada Biosciences, a once high-flying biotech firm that went out of business in 1992. The process calls for single cells to be separated from a growing calf embryo. Each cell is then injected into an unfertilized egg and implanted in the womb of a surrogate cow. Because the nucleus of the unfertilized egg is removed beforehand, it contains no genetic material that might interfere with the development of the embryo. In theory, then, it ought to be possible to extract a 32- cell embryo from a prize dairy cow and use it to produce 32 identical calves, each brought to term by a less valuable member of the herd. In practice, however, only 20% of the cloned embryos survive, meaning that instead of 32 calves, researchers generally end up with only five or six. While the success rate may improve, at present this method of cloning does not seem much better than embryo splitting, which typically produces twins and sometimes triplets. There have been other problems as well. Some of the calves produced have weighed so much at birth that they have had to be delivered through caesarean section. When cattle cloning is perfected, it may not be welcomed down on the farm. Using cloning to create large numbers of identical calves runs counter to what breeders strive to do. Breeders want to create cows better than even their prizewinners, and the only way to do that is by constantly reshuffling the genetic deck with a fresh supply of genes.

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::Cloning:: - Mount Holyoke College

"Clones can think creatively. You will find that they are immensely superior to droids." Lama Su, to Obi-Wan Kenobi[src]

A batch of clone troopers during the early stages of their development on Kamino

Cloning was the process of creating a biological replica of a living creature. That replica could be absolutely identical to its template or modified purposefully. For example, a clone could be made to grow at twice the rate of its template's aging.[1] The genetic structure of a clone could also be altered to make it more obedient than the original host.[2]

The Kaminoans, a species from the watery planet of Kamino, were reputed for their advanced cloning skills. Unknown to the Galactic Senate and the Jedi Council, the Kaminoans created an army of human clones for the Galactic Republic.[2] As soldiers, the clone troopers fought for the Republic in a conflict that, because of the soldiers involved, came to be known as the Clone Wars.[3]

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Cloning - Wookieepedia - Wikia