Lesson 4 Stem Cells and Cloning
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Stem Cells and Cloning
It is unfortunate that the term "cloning" refers to three very different procedures with three very different goals. It is also unfortunate that the first thought many people have when they hear the term is of horror movies which have showed the creation of human monsters or of armies of superhuman soldiers. Reality of cloning is very different.How does society make reliable decisions when stem cell research and cloning are not understood?
1. In lesson 4, students will have the opportunity to apply their knowledge of stem cells to the questions about cloning.
Revisit the basic understanding of stem cells and what they are capable of doing as well as their origins.
What are stem cells?
A stem cell is a primitive type of cell that can be coaxed into developing into most of the 220 types of cells found in the human body (e.g. blood cells, heart cells, brain cells, etc). Some researchers regard them as offering the greatest potential for the alleviation of human suffering since the development of antibiotics. Over 100 million Americans suffer from diseases that may eventually be treated more effectively with stem cells or even cured. These include heart disease, diabetes, and certain types of cancer.
Stem cells can be extracted from very young human embryos -- typically from surplus frozen embryos left over from in-vitro fertilization procedures at fertility clinics. There are currently about 100,000 such embryos. Stem cells can now be grown in the laboratory, so (in a pinch) much further research can be done using existing stem cells; no further harvesting needs to be made from embryos.
Stem cells can also be extracted from adult tissue, without harm to the subject.
Research using stem cells has been authorized in Britain, but was halted in the U.S. by President George W. Bush. He decided on 2001-AUG-9 to allow research to resume in government labs, but restricted research to use only 72 existing lines of stem cells. By 2003-MAY, most of these lines had become useless; some of the lines are genetically identical to others; only 11 remain available for research. Research continues in U.S. private labs and in both government and private labs in the UK, Japan, France, Australia, and other countries. On 2002-SEP, Governor Davis of California signed bill SB 253 into law. It is the first law in the U.S. that permits stem cell research.
HANDOUT #1 - Stakeholders
3. PETA member
For every animal successfully cloned, it’s estimated that 98 animals die. This is important. The animals used are caged, manipulated, and seen as tools to achieve a high-profile and lucrative end. What will happen to the surrogate mothers? Will she go to a good home or will she spend her remaining years as an imprisoned, unwilling surrogate? How many other surrogates failed the test and remain in the laboratory to be used again or killed?
4. Therapeutic cloning (a.k.a. Biomedical cloning)
This is a procedure whose initial stages are identical to adult DNA cloning. However, the stem cells are removed from the pre-embryo with the intent of producing tissue or a whole organ for transplant back into the person who supplied the DNA. The pre-embryo dies in the process. The goal of therapeutic cloning is to produce a healthy copy of a sick person's tissue or organ for transplant. This technique would be vastly superior to relying on organ transplants from other people. The supply would be unlimited, so there would be no waiting lists. The tissue or organ would have the sick person's original DNA; the patient would not have to take immunosuppressant drugs for the rest of their life, as is now required after transplants. There would not be any danger of organ rejection.
5. Society, Religion & Technology Project
In September 2002 Dr Donald Bruce, Director of the Society Religion and Technology Project of the Church of Scotland addressed United Nations delegates in New York to support a global ban on human reproductive cloning on the eve of a crucial UN committee vote. The UN committee responsible for technology was debating a joint proposal by the German and French Governments for a UN treaty which would make any attempt to clone babies illegal worldwide. The proposal has widespread support among UN member states, but is currently stalled by opposition from the USA and some other countries.
6. American Zoological Society
One of the main goals of the American Zoological Society is to educate the public in regards to Conservation of Animal diversity in the world. A technique that has been used in recent years is cloning of extremely rare animals that do not successfully breed in captivity and the wild populations are being reduced quicker than regeneration. Cloning is a valuable source for zoos and aquariums to produce viable animals in species of concern.
Attachment #1- Embryonic Cloning
What is embryo cloning?
Embryo cloning might be more accurately called "artificial twinning", because it simulates the mechanism by which twins naturally develop. It involves removing one or more cells from an embryo and encouraging the cell to develop into a separate embryo with the same DNA as the original. It has been successfully carried out for years on many species of animals. Some very limited experimentation has been done on human embryos. Nature itself is the greatest cloning agent. In about one of every 75 human conceptions, the fertilized ovum splits for some unknown reason and produces monozygotic (identical) twins. Each has an genetic makeup identical to the other. In cloning, this same operation is done intentionally in a laboratory.
How human embryo cloning would be done
Human embryo cloning starts with a standard in vitro fertilization procedure. Sperm and an egg cell are mixed together on a glass dish. After conception, the zygote (fertilized egg) is allowed to develop into a blastula (a hollow mass of cells). The zygote divides first into two cells, then four, then eight... A chemical is added to the dish to remove the "zona pellucida" covering. This material provides nutrients to the cells to promote cell division. With the covering removed, the blastula is divided into individual cells which are deposited on individual dishes. They are then coated with an artificial zona pellucida and allowed to divide and develop. The experiment by Sillman et al. showed that the best results could be obtained by interrupting the zygote at the two cell stage.
Many of these pairs of zygotes were each able to develop to the 32 cell stage, but stalled at that point. They might well have had the potential to develop further and even mature into a viable fetus, except that the original ovum was defective and would have died anyway. For ethical reasons, the researchers had selected embryos which had no possibility of ever maturing into fetuses, and thus becoming newborn babies.
History of embryo cloning:
Cloning of embryos has been used in mice experiments since the late 1970's, and in animal breeding since the late 1980's. The procedure splits a single fertilized ovum into two or more clones, each of which is then implanted into the womb of a receptive female.
However, research into cloning of human embryos has been restricted in the United States and in some other countries. Pro-life groups which oppose free access to abortion have had considerable political power. They were able to have all human embryo research banned by the Regan and Bush Presidencies during most of the 1980's and into the early 1990's. During the first few days of President Clinton's presidency, the ban on public funding of human embryo and fetal research was lifted.
We may not know the individual or team who first performed cloning of human embryos. The methods used have been understood for many years and actually used to clone embryos in cattle and sheep. It is likely that someone had successfully used the method on a human embryo in secret. The first publicly announced human cloning was done by Robert J. Stillman and his team at the George Washington Medical Center in Washington D.C. They took 17 genetically flawed human embryos which would have died within days no matter how they were treated. They were derived from an ovum that had been fertilized by two sperm. This resulted in an extra set of chromosomes which doomed the ovum's future. None could have developed into a fetus. These ovum were successfully split in 1994-OCT, each producing one or more clones. The main motive of the experiment seems to have been to trigger public debate on the ethics of human cloning.
Dr. Steven Muller headed a panel in the US whose mandate was to produce preliminary cloning guidelines. These would be used by the Federal National Institutes of Health to decide which cloning research to fund. The panel recommended that studies be normally limited to the use of preexisting, spare embryos - those that developed during in vitro fertilization procedures that had been performed to assist couples in conceiving. Generally about 20 or 24 ova are fertilized during these procedures. Only three or four are implanted in the woman. The extra zygotes are either discarded or frozen for possible future use. New embryos would only be prepared and used if needed for "compelling research."They further recommended that any studies be normally terminated within 14 days of conception. Some experiments might be authorized to continue until the 18th day, but no further. At that gestational age, neural tube closure begins; this is the start of the development of a nervous system. They recommended that certain procedures be banned, including implanting human embryos in other species, implanting cloned embryos into humans, the transfer of a nucleus from one embryo to another, and the use of embryos for sex selection.
Is embryo cloning moral?
Cloning of animals seems to have a number of potentially positive results:
Scientists are attempting to create transgenic pigs which have human genes. Their heart, liver or kidneys might be useable as organ transplants in humans. This would save many lives; thousands of people die each year waiting for available human organs. Once achieved, transgenic animals could be cloned to produce as many organs as are needed. Experience gained in cloning may add to our understanding of genetics. Researchers have produced transgenic animals. These are genetically altered, typically in order to produce human hormones or proteins in its milk. These materials can be separated from the milk and used to heal humans. Cloning would produce as many genetically altered animals as are needed. The alternative is to simply allow them to mate; this would produce many offspring that had lost the inserted human gene and thus would be unable to produce the medication.
Embryo cloning of humans: Some scientists believe that embryo cloning and related research is moral and might eventually lead to very positive results:
It might produce greater understanding of the causes of miscarriages; this might lead to a treatment to prevent spontaneous abortions. This would be of immense help for women who cannot bring a fetus to term. It might lead to an understanding of the mechanisms by which a morula (a mass of cells that has developed from a blastula) attaches itself to the wall of the uterus. This might generate new, effective contraceptives that exhibit very few side effects. The rapid growth of the human morula is similar to the rate at which cancer cells propagate. Cancer researchers believe that if a method is found to stop the division of a human ovum then a technique for terminating the growth of a cancer might be found.
Parents who are known to be at risk of passing a genetic defect to a child could make use of cloning. A fertilized ovum could be cloned, and the duplicate tested for the disease or disorder. If the clone was free of genetic defects, then the other clone would be as well. The latter could be implanted in the woman and allowed to mature to term. In conventional in vitro fertilization, doctors attempt to start with many ova, fertilize each with sperm and implant all of them in the woman's womb in the hope that one will result in pregnancy. But some women can only supply a single egg; her chances of becoming pregnant are slim. Through the use of embryo cloning, that egg might be divisible into, say, 8 zygotes for implanting.
Fertilized ova could be cloned into multiple zygotes; one could be implanted in the woman and allowed to develop into a normal baby; the other zygotes could be frozen for future use. In the event that the child required a bone marrow transplant, one of the zygotes could be taken out of storage, implanted, allowed to mature to a baby and then contribute some of its spare bone marrow to its (earlier) identical twin. Bone marrow can be harvested from a person without injuring them. A woman could prefer to have one set of identical twins, rather than go through two separate pregnancies. She might prefer this for a number of reasons: to minimize disruption to her career .to make a normal vaginal delivery possible (twin fetuses are smaller than a single fetus; delivery of a larger, single fetus might be impossible because of her shape she might prefer to only have to endure the discomfort of a single pregnancy she might wish to have children that could contribute a kidney to their sibling, if needed. Through embryo cloning, she could be assured that she would deliver identical twins. Some individuals and groups have expressed concerns about adverse effects of embryo cloning in humans, and question its morality:
The genetic screening test described above could also be used to eliminate zygotes of a particular gender, without requiring a later abortion. When the gene or genes that determine sexual orientation are located, cloning could also be used to eliminate zygotes of a particular sexual orientation. A country might finance a program similar to that of Nazi Germany whereby humans were bred to maximize certain traits. Once the "perfect human" was developed, embryo cloning could be used to replicate that individual and conceivably produce unlimited numbers of clones. The same approach could be used to create a genetic underclass for exploitation: e.g. individuals with sub-normal intelligence and above normal strength. There is always the possibility of injuring or killing embryos. Most pro-life supporters believe that an embryo is a human person. During embryo cloning, they would be subjected to assault with the possibility of being murdered. The embryos would be treated as a commodity to be exploited, not as a person.
Attachment #2 – Adult DNA Cloning
What is adult DNA Cloning?
Adult DNA cloning involves removing the DNA from an embryo and replacing it with the DNA from an adult animal. Then, the embryo is allowed to develop into a new animal with the same DNA as the donor. It has been used to clone a sheep and other animals. It has not been tried on humans.
How adult DNA cloning is done:
With the exception of the sperm and egg, every cell in the body contains all of the genetic material in its DNA to theoretically create an exact clone of the original body. But cells have been "biochemically programmed to perform limited functions." The other functions are turned off. Most scientists had believed that such differentiated cells could not be reprogrammed to be capable of behaving as a fertilized egg.
In the case of the sheep "Dolly" (described below), a cell was taken from the mammary tissue of a mature 6 year old sheep while its DNA was in a dormant state. It was fused with a sheep ovum which had had its nucleus removed. The "fertilized" cell was then stimulated with an electric pulse. Out of 277 attempts at cell fusion, only 29 began to divide. These were all implanted in ewes. Thirteen became pregnant but only one lamb, Dolly, was born.
Similar experiments to clone mice were initially unsuccessful. One speculation was that the DNA in sheep may not be used by the cells until after three or four cell divisions have completed. This would give the ovum "sufficient time to reprogram the DNA from [its original] mammary cell functions to egg cell functions." 1 Both human and mouse use the DNA after the second cell division. So, some researchers had predicted that humans as well as mice may not be "clonable". However, mice were successfully cloned later. Thus, cloning of humans might also be possible.
Scientists wondered whether "Dolly" would be fertile. Some cloned frogs are infertile. Also, cells seem to have an internal clock that causes them to die off after a normal life. Since Dolly was conceived from a 6 year old cell, her life expectancy may be reduced from about 11 to only 5 years. This did not take place. Dolly, currently 4.5 years of age, continues to live a normal life.
History of cloning using adult DNA:
1997: This was assumed to be impossible in all mammals, until it was achieved in 1996-JUL by a scientist from the UK, Dr. Ian Wilmut of the Roslin Institute in Roslin, Scotland. News of the experiment was communicated to the press on 1997-FEB-23. "Dolly," a seven-month old sheep, was displayed to the media; she is the first large cloned animal using DNA from another adult. Since Dolly's conception, the Institute has successfully cloned seven sheep of three breeds. The technique that they developed can probably be applied to other domesticated mammals, perhaps including humans.
On 1997-MAR-4, apparently in reaction to "Dolly", President Clinton ordered a widespread ban on the federal funding of human cloning in the US. Research continues in other countries.
1998:On 1998-JUL-22, Dr. Ryuzo Yanagimachi of the University of Hawaii announced the cloning of mice. The team had produced 22 mice; seven of them are clones of clones from the cells of a single mouse.
Japanese researchers from Kinki University in Nara, Japan cloned 8 calves from a single adult cow's DNA. They used techniques similar to that which produced "Dolly." Four died shortly after birth due to what the researchers called "environmental factors." Their study was published in the issue of Science magazine published on DEC 9, ‘98.
On 1998-DEC-14, researchers at the Infertility Clinic at Kyeonghee University in Korea announced that they had successfully cloned a human. Scientists Kim Seung-bo and Lee Bo-yeon took an ovum from a woman, removed its DNA and inserted a somatic cell from the same 30 year old woman. Their report states: "We were able to confirm division up to the fourth cell stage, the stage of embryo development when a test tube embryo is usually placed back in the uterus, where it then further develops into a fetus." The goal of their research was not to clone humans, but to clone specific, genetically identical organs for human transplant. They did not implant the morula into a human uterus because of ethical considerations. They destroyed it. The Korean Federation for the Environmental Movement (KFEM) immediately issued a statement criticizing the study. Members of the Life Safety Ethics Association held a protest demonstration in front of the university.
Public opinion is having a chilling effect on cloning research in North America. Dr. Alan DeCherney of the University of California at Los Angeles said that if anyone tried to clone humans, they would "become the Dr. Kevorkian of reproduction."
2000:By the end of the year 2000, eight species of mammals have been cloned, including mice, cows, rhesus monkeys, sheep, goats, pigs, and rats. Between 3,000 and 5,000 cloned animals have been produced to date.
Current speculation is that the cloning process seems to create random errors in the expression of individual genes. The egg must have its genes reprogrammed in minutes or hours during the cloning process. Ova normally take years to ripen naturally in the ovaries. It appears that the extremely fast rate of programming can produce random errors in the clone's DNA.
Is adult human DNA cloning possible?
One of many concerns with human cloning is that cloning of animals sometimes cause fetal overgrowth (aka large-offspring syndrome.) The fetus grows unusually large and generally dies just before or after birth. They have under-developed lungs and reduced immunity to infection. Duke University researchers announced on 2001-AUG-15 that this particular problem would not exist in humans. The DNA of all primates, such as humans, monkeys and apes, have two copies of a gene that regulates fetal growth, whereas almost all other animals have only one. This spare copy should prevent fetal overgrowth in cloned human fetuses. Randy Jirtle, professor of radiation oncology at Duke University in Durham, NC, said: "It's going to be probably easier to clone us than it would be to clone these other animals because you don't have this problem -- not easy, but easier.'' Kevin Eggan, of MIT's Whitehead Institute works with cloned mice. He called the Duke study "interesting from the perspective of the evolution of imprinting genes." But he cautioned that there is no proof that abnormally large babies are born as a result of this one genetic difference. His lab has a "four-times normal size" mouse clone, which has normal IGFR2R genes. He suggests that there are other factors that can contribute to abnormal development in clones.
Plans to attempt human DNA cloning:
Richard Seed, a physicist from Illinois, attempted to establish a human cloning clinic. He claimed on 1998-JAN-7 that he was "90% complete" in hiring a team of experts to attempt the cloning of a human being, following the experiments on "Dolly." If successful, the resultant child would have identical DNA to one of its parents. Lord Robert Winston, a London based fertility expert who helped produce the first test-tube baby in 1978, said: "My first reaction is that here is somebody who is trying to make a quick buck off of self-advertising, because of course there is no way you could clone a human being safely at this point. I think the man is clearly unhinged and I don't think he is to be taken seriously."
Mr. Seed responded: "I can't really answer the critics who think it's a bad idea. They'll never be persuaded. As far as I'm concerned, they have rather small minds and a rather small view of the world and a rather small view of God." 6 Dr. Seed apparently did not succeed in his project.
As of 2001-AUG, there are two publicized projects underway to clone humans. There may be others which are secret:
Dr. Panayiotis Zavos of the Andrology Institute in Lexington KY and Dr. Severino Antinori, a fertility doctor in Rome announced in early 2001 that they want to proceed with the cloning of humans. Professor Antoniori announced in early 2001-AUG that he intends to start cloning human embryos before the end of 2001.".. a religious sect called the Raelians insists it will shortly undertake the same project. The Raelian sect believes, among other things, that human beings were created in laboratories by extra-terrestrials, and that the resurrection of Jesus was a cloning procedure! Donors and surrogate mothers have already lined up to pay $250,000 for the actual cloning experiment." "In an effort to stall these attempts, Congress is planning to pass a bill banning human cloning by any organization in the United States. However, it is unlikely that this will prevent these efforts from being made elsewhere."
On 2001-AUG-14, Nobel Prize-winning scientist Sir Joseph Rotblat said that our understanding of cloning is "too meager" at this time to succeed. He suggested that many of the scientists involved are motivated by money. He said: "Inevitably the problems will be overcome, and it's then that the real ethical problems begin." He suggested that ethics evolve: "Ethics are not absolute. Look at in-vitro fertilization. This was originally considered unethical but is now widely accepted..."I feel that this [cloning], too, will become acceptable.“
In early 2002-APR, Dr. Severino Antinori announced that a woman who joined his program for infertile couples is now eight weeks pregnant with a fetus derived by human reproductive cloning. Although such cloning is banned in Italy where he lives, he was allegedly able to go to another country to perform the experimental technique. If the woman's pregnancy produces a live newborn, it will probably suffer from one or more serious genetic disabilities.
Is adult human DNA cloning moral?
Some say yes:
Some talents seem to be genetically influenced. Musical ability seems to run in families. Cloning using the DNA from the cell of an adult with the desired traits or talents might produce an infant with similar potential. A heterosexual couple in which the husband was completely sterile could use adult DNA cloning to produce a child. An ovum from the woman would be coupled with a cell from the man's body. Both would contribute to the child: the woman would provide the "factory" for creating cells; the man would provide the "genetic information." They might find this more satisfactory than using the sperm of another man. Two lesbians could elect to have a child by adult DNA cloning rather than by artificial insemination by a man's sperm. Each would then contribute part of her body to the fertilized ovum: one woman would donate the ovum, which contains some genetic material in its mitochondria; the other woman the nuclear genetic material. Both would have parts of their bodies involved in the conception. They might find this more satisfactory than in-vitro fertilization using a man's sperm.
Some say no:
There is no guarantee that the first cloned humans will be normal. The fetus might suffer from some disorder that is not detectable by ultrasound. They may be born disabled. Disorders may materialize later in life. Such problems have been seen in other cloned mammals. There is no reason to assume that they will not happen in humans. Cells seem to have a defined life span built into them. "Dolly" was created from a cell that was about six years old; this is middle age for a ewe. There were some indications that Dolly's cells were also middle-aged. She was believed to be, in essence, about six years old when she was born. She was expected to live only for five years, which is shorter than the normal life span of 11 years. If this is also true of humans, then cloned people would have a reduced life expectancy. The cloning technique could take many years off their life. [These fears proved to be unfounded. "Dolly" has grown into a comfortable middle age with signs of normal aging for her age.] Dolly was conceived using a ewe's egg and a cell from another ewe's body. It is noteworthy that no semen from a ram was involved. If the technique were perfected in humans, and came into general usage, then there would be no genetic need for men. All of the human males could be allowed to die off. [The author of this essay is a male and does not think kindly of such a future. However, some readers might not object to this eventuality.] Large scale cloning could deplete genetic diversity. It is diversity that drives evolution and adaptation. It prevents an entire species from disappearing because of susceptibility to a disease.
[It is doubtful that cloning would ever be used at a level to make this a significant threat.] Some people have expressed concern about the effects that cloning would have on relationships. For example, a child born from an adult DNA cloning from his father would be, in effect, a delayed twin of one of his parents. That has never happened before and may lead to emotional difficulties. There are religious objections to cloning. Most pro-life supporters believe that a fertilized ovum is a full human person. When its nucleus is removed during cloning, that person is, in effect, murdered. A secondary concern is the whole business of collecting surplus embryos and simply storing them in a deep-freeze as a commodity. Some claim that cloned humans may be born without souls. They speculate that the soul enters the body when a sperm fertilizes an ovum. Since there is no sperm involved in cloning, perhaps the fetus would develop without a soul. There is no way to know whether a soul is present; it has no weight, it cannot be seen, touched, smelled, heard, or detected in any other way. In fact, many people believe that souls do not exist. Speculation on this topic can never be resolved. At the current stage in cloning research using adult DNA, the random appearance of genetic defects, noted above, appears to be an overwhelming problem. Such dangers would seem to put an indefinite halt on all ethical cloning of humans.
Attachment #3 - PETA
Put the Kibosh on Cat Cloning
by Kathy GuillermoOn the same day that experimenters at Texas A&M University announced that they had cloned a kitten, animal shelters across the country destroyed more than 6,000 cats. It’s estimated that an equal number of cats died on the streets that day, crushed beneath cars, killed by other animal, or taken out by diseases that make their final hours a nightmare of pain.By the end of this year, more than 4 million cats will die for want of a good home. So I wonder, when Texas entrepreneur John Sperling was writing out the check to university experimenters, did he consider how that money might have helped cats already on this Earth? Rather than creating more felines, his $3.7 million could have done a lot for cats so desperately in need of help.The facts reveal that the motive for the cloning has more to do with seeking profits and headlines than warming the heart. Sperling and a business partner have created a company, Genetics Savings & Clone, which will own the patents on cloning procedures developed at the university. The company has already had more than 10,000 inquiries about cloning companion animals, and a company spokesperson says that the price tag for cloning will be in the “low six figures.”If Sperling does launch a pet-cloning business, he should be up front with his clients. Cloning is a very uncertain science. The journal Science reported last year that most cloned animals have abnormalities that aren’t initially apparent.The most famous clone, Dolly the sheep, has arthritis even though she’s only 6 years old. Or is she? Her creators admit that they are uncertain about how old Dolly really is. They aren’t sure if they should measure her age by her years on Earth because she appears to be the age of her “mother’s” cells.
For every animal successfully cloned, it’s estimated that 98 animals die. This is important. No matter how cute “cc:” the cloned kitty is, she is a product of experimentation. The animals used are caged, manipulated, and seen as tools to achieve a high-profile and lucrative end. What will happen to her surrogate mother? Will she go to a good home now, or will she spend her remaining years as an imprisoned, unwilling surrogate? How many other surrogates failed the test and remain in the laboratory to be used again or killed? How many deformed kittens died before or soon after birth?Though I object to all laboratory studies on animals because they cause such immense suffering to our fellow beings, this animal experimentation does not even pretend to save human or animal lives. Why is cc: considered valuable while the cats used to create her are expendable?It is understandable that some people fantasize about replicating an adored dog or cat. Cloning, however, cannot replicate a particular animal. If it’s successful, cloning can only replicate genetic material—and even this is uncertain. Just as identical twins are different people, so, too, will cloned animals develop different personalities. As one of the cloning experimenters admitted, they cannot “resurrect” animals.Anyone thinking about cloning a beloved animal should go immediately to a local animal shelter or rescue group. You won’t get a duplicate, but there are so many dogs and cats just waiting to love and be loved. John Sperling and Texas A&M experimenters may not care about these animals, but the rest of us can and should.
Attachment #4 – Therapeutic cloning (a.k.a. Biomedical cloning)
How is therapeutic cloning done?
I once had a Swedish ivy plant, and about a dozen empty flower pots. I cut off many leaves from the original plant, placed each of them in a pot filled with damp soil, and surrounded the pots with clear plastic. In a few weeks, I had a dozen new plants. This shows that all of the material and information needed to create a Swedish ivy plant is contained in a single leaf. Actually, it is contained in a single cell of a single leaf.
So too, all the information needed to create a new human being is contained in each cell of an existing human being. DNA testing on an human often starts by scraping some cells from the inside of a person's mouth. Living cells can be scraped off of a person's skin. No matter how a cell is obtained, it contains the DNA of the person, and thus contains all of the information required to produce a duplicate or cloned person. Each cell is, in fact, a form of human life for the simple reason that it contains human DNA
A woman's ovum also contains her DNA. What is involved in somatic cell nuclear transfer is to:
Take a woman's ovum, and remove its DNA. This converts it to a form of human life into what is basically a factory for creating a pre-embryo.
Remove the DNA from a cell taken from a human, and inserting it into the ovum.
Giving the resulting ovum an electrical shock to start up its embryo making operation. In a small percentage of cases, a pre-embryo will be formed.
The pre-embryo is allowed to develop and produce many stem cells. So far, the procedure is identical to that used in adult DNA cloning. However, the pre-embryo is not implanted in a woman's womb in order to try to produce a pregnancy.
Stem cells are removed from the pre-embryo; this results in its death.
The stem cells would be encouraged to grow into whatever tissue or organ is needed to treat the patient. Stem cells are a unique form of human cell that can theoretically develop into many organs or body parts the body.
The tissue or organ would be transplanted into the patient.
An important factor to remember is that:
The original seed cell is a form of human life; it contains human DNA, whether it comes from a skin scraping or is extracted from the inside of a person's mouth. The original ovum is a form of human life; it contains human DNA. The pre-embryo that is produced is a form of human life; it contains human DNA. So, there is a continuity of human life from a surplus cell which a human produces by the millions each day, to the pre-embryo.
Theoretically, these stem cells can be used to develop into replacement organs (heart, liver, pancreas, skin, etc) Therapeutic cloning has not yet been accomplished in the laboratory or clinic.
Future experiments may not succeed. There were four main hurdles to overcome:
Stem cells have to be "successfully isolated and grown in the laboratory." This has already been accomplished They have to be encouraged to "turn into specific cell types." This has been done for most of the 220 cell types in the human body. They have to be proven usable in treating patients with diseases, injuries, or disorders. The transplanted tissue must develop normally and must not represent significant "risks to the patient." If scientists are successful, it would probably take many years of research before the first useful results will be obtained.
What are its possible benefits?
If therapeutic cloning using embryos is successful, then perfectly matched, replacement organs could become freely available to sick and dying people. That would save countless numbers of lives, and increase the quality of life of countless others. Three possible examples of therapeutic cloning "might include the use of insulin-secreting cells for diabetes; nerve cells in stroke or Parkinson’s disease; or liver cells to repair a damaged organ."There would probably also be side benefits resulting from the research. "Further advances in understanding of how organs regenerate would increase the range of possible treatments that could be considered."
In the United States during 1998, "More than 50 disease advocates and scientific societies, representing such concerns as diabetes, blindness, Parkinson's disease, glaucoma, AIDS, Down Syndrome, cystic fibrosis, stroke, lymphoma, infertility and cancer--as well as professional groups that focus on such issues as cell biology, aging, microbiology, ophthalmology, cardiology, pediatrics and reproductive medicine--recently sent a letter to members of Congress urging them to support federal funding for...[stem cell] research."
This procedure would have a number of advantages, when compared to regular organ transplant donated by a second person:
There would be presumably be no danger of rejection of the transplant because the organ's DNA would match the patient's DNA exactly. For transplants involving kidney (or theoretically any other organ that is duplicated in the body), another individual would not have to experience pain, inconvenience, and potentially shortened life span in order to donate the organ. The patient would not have to wait until an unrelated donor dies to obtain a transplant. A new organ could be grown for them as needed. The patient would not have to make-do with a replacement organ that is old and may have reduced functionality; a brand-new organ would be grown specifically for them. The procedure would save lives which would otherwise be lost waiting for a transplant that did not come in time. The potential exists to cure, or at least treat, certain diseases and disorders that cannot be effectively handled today.
What are the problems of therapeutic cloning:
Before therapeutic cloning can become generally available to cure heart disease, diabetes, paralysis, etc., a number of hurdles have to be overcome:
Developing cures: Methods have to be developed that will cure or treat diseases with embryonic stem cells. This looks promising. Research with adult stem cells, which has been underway for many years, have shown great promise. Unfortunately, adult cells are limited in their application. Research using therapeutic cloning is a new field, but it has already shown that stem cells from embryos have much greater flexibility than adult stem cells.
Is an embryo a human person? Pro-life supporters generally believe that a human person comes into existence at conception. Some believe that somatic cell nuclear transfer is sufficiently similar to normal conception with an egg and spermatozoa that a human person also comes into existence during therapeutic cloning. The process of extracting stem cells involves killing the embryo. To many pro-lifers, this is murder. They feel that murdering one person, the embryo, to cure another person of paralysis, or diabetes, or heart disease, etc. can never be justified. More details. Therapeutic cloning research may well be limited to those countries, like China, the UK, and perhaps Canada, where pro-life supporters are relatively few in number.
Stability of stem cells: As of 2003-MAR, therapeutic cloning is still in its early stages of development. Stem cells have sometimes mutated, and thus been rejected by the recipient's body. In other cases, at least with experiments on animals, they have produced tumors. It is obvious that therapeutic cloning will not be feasible until these deficiencies have been overcome.
Where would the eggs come from? At the present stage of somatic cell nuclear transfer, Thomas Okarma, chief executive of Geron Corporation -- a leading stem-cell research establishment -- estimated that takes "100 eggs if you're lucky" to produce a useable stem cell line. This means that if a cure for diabetes involving therapeutic cloning is found, it would take 1.5 billion eggs to cure the 15 million Americans who have diabetes. Until the production of stem cells becomes more efficient, very few cures could be made for economic reasons. Even if and when techniques are found to reliably produce one custom stem cell line for each egg harvested from a woman, 15 million eggs would be required to completely wipe out diabetes. Extracting eggs from women is "painful, costly and unreliable." Focus on the Family, a Fundamentalist Christian group, cited an unknown expert who has said that the process of harvesting eggs would seriously injure about one percent of all female donors. We have been unable to determine what form this injury might take. Assuming two dozen eggs per woman, this would still require over a half million women willing to donate eggs and run the risk of some type of injury. Therapeutic cloning will probably only become generally useful when a method is found to use non-human eggs as source material. Research is underway to use rabbit eggs. During the process, "the embryo will lose all traces of its rabbit origin."
Attachment #5 – Society, Religion & Technology Project
Should we Clone Animals?
In our opinion while all the media attention focused too much on speculations about human cloning, which may never happen, it largely lost sight of the fact that we already can clone animals which raises important ethical questions also. These are explored in our paper Should we Clone Animals?.
In same edition of the scientific journal Nature in July 1998 that confirmed that Dolly was real, and another article announced that researchers in Hawaii had cloned mice. This greatly opens up the possibilities for worldwide cloning research, but also presents potential problems. We discuss the implications in our brief article Cloned Mice - Is the sky now the limit for cloning? Mice are easier to handle and have been used to investigate whether cloning affects the factors which control ageing. Recent experiments showed that cloned mice die much younger than ordinarily mated mice. This needs to be followed up with further studies but it raises a major question about the cloning process.
As the range of animals which has been cloned has increased, so the reasons for doing attempting it have become more improbable. Cloning to preserve an endangered species of cow did not succeed, might be a laudable if unlikely objective. Cloning a cat to "restore" a lost pet surely makes reproductive science look ridiculous, see Cloned Cat is Cute but Ethically Unacceptable.
Animal Welfare Concerns
A series of animal welfare concerns prompted SRT responses on Mouse Clones Die Young and Dolly's the Cloned Sheep's Arthritis. We have a recent overview of these issues in an article Animal Welfare and Pet Cloning Ethics. In parallel with the 1998 human cloning consultation the Farm Animal Welfare Council (FAWC) also ran a public consultation on animal cloning, to which the SRT Project also made a substantial submission. SRT's initial response is given on Cloning, Ethics and Animal Welfare - SRT Comment on Farm Animal Welfare Council Report.
Pig Cloning for Xenotransplantation - Cautious Hopes and Ethical Doubts
Xenotransplantation could one day mean a new lease of life for some. The announcement on 14 March 2000 that PPL's US company had cloned 5 pigs successfully could mark an important step in research towards overcoming rejection of pig's organs. This was followed in January 2002 by two announcements of "Knockout" Pigs , where cloning was used to enable a gene to be deleted which might overcome one of the rejection mechanisms.
Our page Should we Clone Humans? was a ground-breaking event for SRT, in that it attracted worldwide attention following Dolly. Since then, we have discussed with many leading experts around the world the basic reasons why our answer is an emphatic "No!". We have gradually been refining the arguments, and updated the article. A fuller discussion appears in chapters on cloning in "Human Cloning - the Religious Aspects" (Westminster John Knox 1997) and "Beyond Cloning" (2001, Trinity Press), and the report Cloning Animals and Humans of the European Ecumenical Commission for Church and Society, to which SRT was the main contributor. The SRT Project wrote a special Report on Cloning to the Church of Scotland's 1997 General Assembly which was passed on May 22 by the church's highest body. A motion was passed calling on the UK Government to take steps to ensure that the routine cloning of animals in meat and milk production is not allowed, while giving support to the work of the Roslin Institute in genetic modification of sheep and other farm animals to produce therapeutic proteins in milk, and a further motion was passed in opposition to the cloning of human beings, while leaving open for the time being possible research uses of cloning technology.
Spurious Claims and Irresponsible Science
Cloned Babies Unethical says Church of Scotland. In the absence of proper proof, the Raelian Society claims to have cloned a baby girl must be treated with scepticism, but in trying to clone humans they are taking unacceptable risks with human beings and acting unethically. We believe there are sound reasons why the cloning of human beings should be regarded as ethically wrong, but any cloned child should not be stigmatised as abnormal. People are also being misled if they are led to believe cloning will recreate a lost child or lead to immortality. The claims are a strong reason why the USA must act quickly to pass domestic legislation to ban reproductive human cloning and to drop its current resistance to a UN worldwide ban. Kirk calls on United Nations to ban Reproductive Cloning We also regard the claim by an Italian scientist that he will clone a baby is highly irresponsible, and goes against established legal, ethical and medical practice. We give our rationale in Cloned Babies - the Height of Irresponsibility. A number of premature claims have been made for the first cloned human embryos, see Comment on the Korean Claim to Clone a Human Early Embryo, Cloned Embryos and Parthenogenesis and Cloned Human Foetus Claim Unlikely.
Cloning Regulation - How Should Society and Nations Decide?
Speculative claims of Dr Antinori, the Raelian Society and Richard Seed have alarmed many and prompt some to assume that humans will inevitably be cloned. But are such claims primarily hype, publicity seeking, or appeals for funding? Can we legislate internationally to outlaw human cloning, and and how should we draw limits on research? Read about our views in Cloning - How Should Society Decide?. There is a pressing need to draw up international research guidelines on cloning Kirk calls for Urgent Cloning LegislationBack to Contents
Stem Cells and Non-reproductive uses of Cloning
In the UK there is a substantial agreement against cloning human beings, and the emphasis has shifted to the complex issues of stem cells and non-reproductive cloning for potential cell replacement therapy. For an overview see the updated SRT information sheet Embryonic and Adult Stem Cells: Ethical Dilemmas covering stem cells, the status of the embryo, the prospects or otherwise for adult stem cells, therapeutic uses of cloning, and the legislative challenges. The major issues are set out in more detail in a discussion paper of the Conference of European Churches working group on BioethicsStem Cells and Embryonic Cloning, of which SRT did the main drafting.
SRT's Director Dr Donald Bruce has been much involved with the emerging European discussion and presented a paper Stem Cells and Cloning - Medical Potential and Ethical Dilemmas at the European Commission's major Conference "Stem Cells: Therapies for the Future?", 18-19 December 2001, Brussels. We also discuss Stem Cells : Are Adult or Placental Cells a Viable Alternative to using Embryos? attempting to clear up some of the confusion over claims and counter claims whethe embryonic stem cell research is necessary or not.
SRT has been involved with the emerging discussion from the outset. It took part in a consultation exercise of the Human Embryology Authority (HFEA) and Human Genetics Advisory Commission (HGAC) on the potential medical uses of cloning technology. On 8 December 1998, they reported the results of this consultation. Our immediate response to the report "Cloning Issues in Reproduction, Science and Medicine" was given in a short press release Cloning Human Embryos for Spare Tissues - an Ethical Dilemma.
In summer 1999, the UK Government set up the Donaldson Committee to examine these issues. In October 1999 SRT and the Board of Social Responsibility of the Church of Scotland made a more substantial submission of our ethical concerns about Human Embryonic Cloning to this committee. We expressed deep concern about proposals to clone human embryos which would be used not for reproduction but as a source of replacement tissues, and call for a much wider public debate of this controversial issue before making its mind up. Need for Wider Public Debate on Therapeutic Cloning. These criticisms were followed a few months later by the setting up of the Donaldson Committee.
On 16 August 2000 the Donaldson Report was finally published. See our Press Release and Background Information
On February 2000, Dr Bruce was invited to the House of Commons to address MP's by the Bio-Industry Association and in December 200 by the Human Genetics Forum (both sides of the debate!). His paper is given in Address to MPs on ethical aspects of therapeutic uses of cloning. In December 2000 and January 2001, the UK Parliament debated the report and voted to allow the cloning of embryos to produce human stem cells for research, and to allow embryo cloning. Was this right or have we opened the door too far? SRT assessed the outcome of the vote in a paper Are Embryonic Stem Cells a Step too Far?
Attachment #6 – American Zoological Society
This Communiqué issue focuses on reproductive technologies, a subject that for me is at once daunting and fascinating. I am not particularly confident with my knowledge of genome banking, in vitro fertilization, and nuclear transfer (cloning), for example, but I tend to get quite enthusiastic about “high technology” and its exciting prospects for the future. So I reviewed the articles in this issue, hoping to increase my knowledge and to come away with great stories about the brave new world of cloning and other ingenious techniques.
Well I did increase my knowledge (which was not so hard, given my starting base), and I know other readers will benefit as well. Readers will see articles thoughtfully and professionally written about complex matters absolutely fundamental to endangered
species reproduction. The authors are precise, helpful and clearly committed to communicating with their fellow professionals. I am grateful for the work these authors do, and for the extra effort they make to advance our collective knowledge.
But with the exception of some hilarious – but real life – stories about sex and animals, I didn’t come away with any fabulous facts about how cloning and other new techniques will revolutionize conservation. And that was because, like many members of the media and public, I had probably gotten naively carried away with exciting reports and hype about such things as cloned pandas and wooly mammoths. The authors brought me back to earth, with good lessons about what is fundamental and realistic.
Each author – whether writing about genome banking, assisted reproduction, cloning or contraception – delivered the same sobering message. While these techniques are of great benefit, and hold considerable promise, they should not exaggerate benefits, ignore current deficiencies, or overshadow fundamental research. Sure cloning is a worthwhile endeavor, but there are very real inefficiencies and problems of disease transfer. Sure in vitro fertilization and embryo transfer techniques are valuable, but they must not displace basic investigations of social interaction, natural courtship and environmental influence. Sure reversible contraception is critical to systematic species conservation, but it must be accompanied by a major education effort to clarify public misconceptions.
So in the end, I came away wiser and more informed. I had been taught once more
the extremely important characteristics of dedicated zoo and aquarium professionals.
Conservation, as practiced by such professionals, is sensible, realistic, honest, responsible, scientifically rigorous, suspect of bravado, built upon experience and (when it
comes to explaining giraffe sex to an embarrassed public) filled with wit and good
S y d n e y J . B u t l e r
E x e c u t i v e D i r e c t o r
Dr. B. Benoit maintains a Web page "HUMAN CLONING AND RE-ENGINEERING" that is dedicated to "the dissemination of information on human embryo cloning research and related topics, with special attention directed [sic] to the moral implications." See: http://cac.psu.edu/~gsg109/qs/emclone.html
Dr. Ray Bohlin, director of communications at Probe Ministries has written an essay: "The Little Lamb That Made a Monkey of Us All - Can Humans be Cloned Like Sheep?", 1997-MAR-7. See: http://www.probe.org/docs/lambclon.htm
"Human Cloning Test Succeeds," Chosun-Ilbo newspaper, 1998-DEC-15
"Humans may be cloned 'Sooner than anyone thinks.' " CNSNews.com at: http://www.mcjonline.com/news/01a/20010213e.shtml
Gina Kolata, "Few cloning efforts work, scientists say," New York Times, 2001-MAR-25.
"Cloning Proponent 'clearly unhinged,' scientist says", Reuters News Agency, 1998-JAN-7
Religion Today news summary, 1998-NOV-18.
Will Dunham, "Scientists tout feasibility of human cloning," Reuters, at: http://dailynews.yahoo.com/h/nm/
"Human cloning easier than thought?," CNN, at: http://www.cnn.com/2001/HEALTH/08/14/
Peter Foote, "Scientist calls for debate on human cloning," Irish Times, at: http://www.ireland.com/newspaper/
"The cloning debates," Editorial at The Buffalo News. See: http://www.buffalonews.com/editorial/
Prasad Venugopal, "The science and politics of genetic engineering," Political Affairs, Vol. 80, #7, 2001-JUL, at: http://www.cpusa.org/pa/0701pa/07gmofood.htm
"Reproductive Cloning: Just What The Doctor Ordered," Washington Update, Family Research Council, 2002-APR-5.
Julie Kimbrough, "New Poll Shows More Than Two Thirds of Americans Support Therapeutic Cloning Research to Produce Stem Cells," Coalition for the Advancement of Medical Research, at: http://www.boston.com/
Pope Paul II, "Address to International Congress on Transplants," 2000-AUG-29, at: http://www.cin.org/pope/organ-transplant-cloning.html
Julie Rovner, " 'Therapeutic' Cloning Wins Key Ally in U.S. Senate," Reuters, 2002-APR-30, at: http://story.news.yahoo.com/news?
"A report from the chief medical officer's expert group reviewing the potential of developments in stem cell research and cell nuclear replacement to benefit human health," Department of Health (UK), at: http://www.doh.gov.uk/cegc/stemcellreport.htm The report is available as an executive summary or as full report in PDF format. You can obtain a free software to read PDF files from Adobe.
"Comment: Stem Cell Research," Mary Woodard Lasker Charitable Trust, at: http://www.fundingfirst.org/comment/16/comm2.html
Cited in "Testimony of James Kelly before the House Government Reform Committee (Subcommittee on Criminal Justice, Drug Policy, and Human Resources)" on 2002-MAY-15, at: http://reform.house.gov/
Charles C. Mann, "The First Cloning Superpower: Inside China's race to become the clone capital of the world," at: http://www.wired.com/wired/
Stuart Shepard, "Cloning Research Found to Hurt Women," Focus on the Family, 2003-MAR-28, at: http://www.family.org/