Cloning

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In biology, cloning is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. Cloning in biotechnology refers to processes used to create copies of DNA fragments (molecular cloning), cells (cell cloning), or organisms. The term also refers to the production of multiple copies of a product such as digital media or software.

Quotes[edit]

A prominent biologist Lee Silver, once said that biology would be forever defined as BD and AD: before Dolly and after Dolly. Such is the enormity of the findings of the Roslin Institute, where not only was Dolly the sheep created, but her predecessors Tracy, Megan and Morag. These animals are important in terms of their significance to science and the ethical issues that their creation raises. ~ BBC
Reproductive cloning is expensive and highly inefficient. More than 90% of cloning attempts fail to produce viable offspring. More than 100 nuclear transfer procedures could be required to produce one viable clone. In addition to low success rates, cloned animals tend to have more compromised immune function and higher rates of infection, tumor growth, and other disorders. ~ Human Genome Project
Claims that you could clone individual treatments of human beings to treat common diseases like diabetes, suggests you need a huge supply of human eggs. Where are they going to come from? Even if you don't have a religious view of the sanctity of life, you have to ask is there going to be a massive trade in human eggs from poor women to rich countries. ~ Helen Wallace
No doubt the person whose experimental skill will eventually bring forth a clonal baby will be given wide notoriety. But the child who grows up knowing that the world wants another Picasso may view his creator in a different light. ~ James Watson
Considered contrary to the moral law, since (it is in) opposition to the dignity both of human procreation and of the conjugal union. ~ Donum Vitae
The delivered kid was genetically identical to the bucardo. In species such as bucardo, cloning is the only possibility to avoid its complete disappearance. ~ Jose Folch
Dr. Josef Mengele: Do you know what I saw on the television in my motel room at one o'clock this morning? Films of Hitler! They are showing films about the war! The movement! People are fascinated! The time is ripe! Adolf Hitler is alive! [Takes photo album and places it on his lap] This album is full of pictures of him. Bobby Wheelock and ninety-three other boys are exact genetic duplicates of him, bred entirely from his cells. He allowed me to take half a liter of his blood and a cutting of skin from his ribs. [laughs] We were in a Biblical frame of mind on the twenty-third of May 1943, at the Berghof. He had denied himself children because he knew that no son could flourish in the shadow of so godlike a father! But when he heard what was theoretically possible, that I could create one day not his son, not even a carbon-copy but another original, he was thrilled by the idea! The right Hitler for the right future! A Hitler tailor-made for the 1980s, the 1990s, 2000! ~ Heywood Gould
The Doctor: She hates her own clones. She burns her own clones. Frankly, you're a career break for the right therapist. ~ Steven Moffat
Developments in biotechnology have raised new concerns about animal welfare, as farm animals now have their genomes modified (genetically engineered) or copied (cloned) to propagate certain traits useful to agribusiness, such as meat yield or feed conversion. These animals have been found to suffer from unusually high rates of birth defects, disabilities, and premature death. ~ Humane Society of the United States
It is also our view that there are no sound reasons for treating the early-stage human embryo or cloned human embryo as anything special, or as having moral status greater than human somatic cells in tissue culture. A blastocyst (cloned or not), because it lacks any trace of a nervous system, has no capacity for suffering or conscious experience in any form – the special properties that, in our view, spell the difference between biological tissue and a human life worthy of respect and rights. Additional biological facts suggest that a blastocyst should not be identified with a unique individual person, even if the argument that it lacks sentience is set aside. A single blastocyst may, until the primitive streak is formed at around fourteen days, split into twins; conversely, two blastocysts may fuse to form a single (chimeric) organism. Moreover, most early-stage embryos that are produced naturally (that is, through the union of egg and sperm resulting from sexual intercourse) fail to implant and are therefore wasted or destroyed. ~ The President's Council on Bioethics
  • The first obstacle to cloning your dog is that $100,000 cost. The second is getting the right kind of cells.
    It's easier if your dog is still alive, in which case you just take it to the vet to get a biopsy sample, an 8-millimeter piece of skin from the abdomen, or about half the width of a penny. Then you pack those samples into an ice-pack-filled plastic-foam box and mail the box to Sooam.
    You can clone a dog that has been dead for fewer than five days, too, as long as you wrap its body in wet towels and place it in a refrigerator, which keeps it from drying out before getting to the vet. If the dog is dead, Sooam asks that you send as many skin samples as possible so that the lab has a better chance of finding living cells.
  • A prominent biologist Lee Silver, once said that biology would be forever defined as BD and AD: before Dolly and after Dolly. Such is the enormity of the findings of the Roslin Institute, where not only was Dolly the sheep created, but her predecessors Tracy, Megan and Morag. These animals are important in terms of their significance to science and the ethical issues that their creation raises.
  • Wilmut has always been clear about his ethical beliefs and has publicly voiced his approval of 'therapeutic cloning', whilst strongly opposing anyone attempting to clone a human, claiming that they are 'very naïve'. He allays any fears that cloning would produce identical humans and explains that unlike identical twins, clones are derived from different eggs, developed in different uterus and most likely have different mothers. However, his condemnation of human cloning lies in both the process and the overall practical benefits. 'I don't like the idea of copying a person' he explains, 'because I think that each child should be wanted as an individual.' There are also practical considerations,
    'we are one of the labs who are trying to clone a pig, with the aim that one day pigs will provide organs for transplantation into human patients - there is a real biological need there. In the process we have probably worked with over four or five thousand embryos without any success. Just where exactly would you get this many human embryos? It is obscene to even think about doing that to people.'
  • Hard lessons have been learnt by past situations involving science and secrecy. Nobel Peace Prize winner Joseph Rotblat said of Dolly's creation that 'it was as important as the building of the atomic bomb.'
  • "First, a suitable surrogate mother animal is required. For the mammoth this would need to be a cow (as best biological fit) but even here the size difference may preclude gestation to term," it said.
  • "If there are intact cells in this tissue they have been 'stored' frozen. However, if we think back to what actually happened to the animal - it died, even if from the cold, the cells in the body would have taken some time to freeze. This time lag would allow for breakdown of the cells, which normally happens when any animal dies. Then the carcass would freeze. So it is unlikely that the cells would be viable," it said.
  • "Let's say that one in a thousand cells were nevertheless viable, practical issues come into play. Given that we have an efficiency of 1% cloning for livestock species and if only one in a thousand cells are viable then around 100,000 cells would need to be transferred," it said.
  • The FDA claims that the scientific evidence shows that food from clones is no different than other food. But any attempt to evaluate the current science on the foods safety of products from clones is doomed to fail, as there have been virtually no peer-reviewed scientific studies designed for evaluating cloned food.
  • Since FDA could not find studies on milk or meat from clones, the Agency chose to assess the safety of these foods indirectly, by looking at studies that investigated basic issues about cloning technology.
  • *For the post-puberty period in cow clones, for example, FDA says that "Most of the possible food consumption risks arising from edible products of clones (E.g., milk or meat) would occur during this Developmental Node," but the Agency notes that "little information is available on animals during this developmental phase, and much of that information comes in the form of single sentences or short mentions in journal articles that address some other issue."
    • Ibid, p.6
  • Hydrops, an abnormality common in cloning in which fluid builds-up in the fetus and/or placenta, can lead to abortion, stillbirths, or early deaths of clones, and usually results in euthanasia of surrogate cows. The incidence of hydrops in cloning is as high as 42%, but in natural breeding or other assisted technologies the condition is extremely rare, with estimates as low as 1 in 7500.
    • Ibid, p.7
  • *FDA notes that "early reports, beginnning in 1998, of clone moraltiy rates were 50 to 80 percent," but states that more recent studies show better results, with mortality rates dropping to around 20%.
    • Ibid, p.11
  • A 2005 study cited by FDA, on semen quality from two clones, found clones has a lower pregnancy rate (55% compared to 63%) than natural comparators and almost double the rate of spontaneous abortions. A 2004 study found that the range of rates of development to blastocyst for embryos fertilized in vitro by sperm from six bull clones was lower than that of comparators, while pregnancy and calcing rates of clones were 83%, compared to 90% for comaprators.
    • Ibid, p.12
  • On meat consumption, FDA notes only that "differences in meat nutrient composition were very small...." But its chart comparing nutrient levels in cloned versus natural pigs shows clones have lower levels of all except one amino acid, while cholesterol and all except two fatty acid levels were higher for clones.The agency offers no explanation or dicussion of these findings.
    • Ibid, p.13
  • FDA's "Animal Health" section for the post-puberty period in pig clones consists of a single sentence: "No reports on aging and maturity in swine clones were identified." The Agency later repeats that it "was not able to identify any peer-reviewed studies on non-reproductive postpubertal studies (sic) in swine clones." Thus, the Agency relies solely on the Viagen data for this period, which, as noted above, consisted of data on just five clones, and found that clones weighed less than natural comparator animals and had reduced marbling and back-fat thickness.
    • Ibid, p.15
  • FDA has a long history of interpreting the definition of a “new drug” broadly, basing it on the functional claim intended from a new technology. Under the FFDCA, new drugs include “articles (other than food) intended to affect the structure or any function of the body of man or other animals.”220 Thus, for example, FDA is currently reviewing genetically engineered (GE) “fast growing” salmon under its “new animal drug” authority, because the GE fish is structurally and functionally affected by the technology. Similarly, cloning companies claim that their technology will affect both the structure and function of the cloned animal, by producing animals with improved meat qualities or high-yielding dairy animals. Furthermore, cloning experts say that the cloning technology is the same in animals as it would be in humans, and FDA has already stated that any human cloning research would be regulated as a new drug by the agency under FFDCA, and would require submission of an “investigational new drug application.”221 FDA offers no explanation as to why animal cloning should be exempted from the rigorous new drug review procedures that it requires for human cloning research.
    • Ibid, p.19
  • Given the paucity of data that directly address the safety of meat and milk from cloned animals, the FDA used indirect measures of food safety, primarily data on the health of the clones at different life stages. The operating hypothesis is the notion that an animal that appears healthy must be safe to eat (e.g. the Critical Biological Systems Approach). This approach is not scientific—this is reasoning by inference, not from data. Furthermore, FDA has bent over backward to interpret data from cloning companies in a way that minimizes the potential problems raised by SCNTs. Both of these problems need to be remedied in the final Risk Assessment.
  • It is clear from studies FDA reviewed on animal health that clones have higher rates of illness and death than non-clone comparators, particularly at the younger ages. This could lead to greater use of drugs on clones, which in turn could exacerbate antibiotic resistance. FDA’s Risk Assessment failed to assess this risk. In both cloned cattle and sheep, one of the biggest health problems is large offspring syndrome (LOS). As the name implies, LOS refers to offspring that are abnormally large at birth, but they also have a range of other abnormalities. FDA lists 11 clinical signs associated with LOS, including fetus weight more than 20% larger than average for the breed, deformities of limb and/or head, disproportionate or immature organ development, increased susceptibility to infection, and cardio vascular problems. Since cattle with LOS tend to have increased susceptibility to infection, there would be a greater need for antibiotics and other drugs to help fight the infections in those LOS cattle. Although LOS doesn’t appear to happen normal reproduction or AI, it does happen with some of the ARTs, such as in-vitro fertilization (IVF), embryo culture, as well as with SCNTs
    • Ibid, p.10
  • In sum, contrary to FDA, we feel the data on offspring of clones are disturbing— particularly the increase in preweaning death rates of offspring of clones compared to offspring of comparators and the increases in the rate blood measurements (both hematology and clinical chemistry) being considered outliers (e.g. extreme values) to increase over time with the offspring of clones while it decreases over time with offspring of comparators. The fact that any differences were seen in offspring of clones compared to offspring of comparators deserves much more scrutiny. Clones are known have much higher preweaning death rates compared to non-clones. The fact that preweaning death rate of offspring of clones was higher, depending on clone source, compared to offspring of non-clones, suggest that some of the adverse health impacts in clones are being passed on to their offspring and so should deserve much more scrutiny. Instead, FDA tries to explain away all this troubling data so that they can conclude that offspring of clones are not that different than offspring of non-clone comparators.
    • Ibid, p.15
  • The notion that clones are “identical twins born at different times” is scientifically wrong and very misleading. There is a fundamental distinction between identical twins produced naturally and a SCNT “clone.” Identical twins normally arise by the splitting of an already fertilized egg, so that the two twins share not only the same genetic complement but also have split the cytoplasm from the egg. With SCNT clones, a very different process takes place (Campbell et al. 1996). The egg [from which the nucleus has been removed] comes from one animal, the nuclear material comes from a somatic cell from another animal. This somatic cell is usually fused with the enucleated egg, and then is stimulated electrically or biochemically, while the resulting embryo, if it starts to grow, is then transplanted into the womb of a third animals which acts as the surrogate mother. Thus, a clone of an existing animal will not share the same egg cytoplasm as the original animal, and, while it might share the genes of the original animal, the fact that a nucleus from a somatic cell has been used means that the genes in the somatic cell are subtly different that genes from a fertilized egg. As the FDA notes, the genes in somatic cells need to be reprogrammed so that they are more like fertilized cells. Indeed, research has suggested that, for proper development to occur, a donor nucleus must undergo a reversal of differentiation and a genome-wide epigenetic reprogramming (Riek et al. 2001). Difficulties in this process are believed to be the cause of the high rate of birth defects, and other health problems, in clones. While the FDA acts like a lot is known about epigenetic reprogramming, the reality is that, some ten years after Dolly, there is still a lot that is not know about epigenetic reprogramming which helps explain why the vast majority (e.g. 95%) of cloned embryos do not survive to adulthood.
    • Ibid, p.16
  • The notion that cloning poses “no unique risks” compared with other artificial reproductive technologies is highly misleading. First, by focusing only on whether or not “unique risks” occur with cloning ignores the importance of quantitative differences in risks between cloning and other reproductive techniques. Over 90% of cloning attempts end in dead animals.
    • Ibid, p.17
  • A number of researchers have noticed similarities between some of the mitochondrial depletion diseases in humans and some of the abnormalities seen in SCNT and hypothesize that aberrant nuclear-mitochondrial interactions in SCNTs could be responsible for some of these abnormalities. A research team in Germany found that “A survey of perinatal clinical data from human subjects with deficient mitochondrial respiratory chain activity has revealed a plethora of phenotypes that have striking similarities with abnormalities commonly encountered in SCNT fetuses and offspring. We discuss the limited experimental data on nuclear-mitochondrial interaction effects in SCNT and explore the potential effects in the context of new findings about the biology of mitochondria” (Hiendleder et al. 2005: 69). Researchers in the United Kingdom have suggested that potential overpopulation of mitochondria could lead to the large offspring syndrome often seen in SCNT cow clones and call for more work in this area: “a cytoplasm over-populated with mitochondria would lead to cellular expansion that might be indicative of the reported large-offspring syndromes. This under-researched area of investigation could provide clear answers to some of the developmental abnormalities witnessed in NT offspring and aborted feotuses, whether mediated through failure of somatic cell reprogramming or independently” (St John et al. 2004: 638-639).
    • Ibid, p.20
  • In sum, there is a unique risk posed by SCNT clones that is not posed by other ARTs (artificial reproductive technologies): the potential for aberrant nuclearmitochondrial interactions. Embryos created via SCNT embryos differ from those created by other ARTs in two ways: they may be heteroplasmic (e.g. contain mtDNA from two sources) and nuclear-encoded mitochondrial DNA transcription and translation factors persist in SCNT, but not IVF, embryos.
    • Ibid p.21
  • Ian Malcolm: God creates dinosaurs. God destroys dinosaurs. God creates man. Man destroys God. Man creates dinosaurs.
Ellie Sattler: Dinosaurs eat man…woman inherits the earth.
  • Considered contrary to the moral law, since (it is in) opposition to the dignity both of human procreation and of the conjugal union.
    • Donum Vitae Congregation for the Doctrine of Faith (1987) [1]
  • The delivered kid was genetically identical to the bucardo. In species such as bucardo, cloning is the only possibility to avoid its complete disappearance.
  • Dr. Josef Mengele: Do you know what I saw on the television in my motel room at one o'clock this morning? Films of Hitler! They are showing films about the war! The movement! People are fascinated! The time is ripe! Adolf Hitler is alive! [Takes photo album and places it on his lap] This album is full of pictures of him. Bobby Wheelock and ninety-three other boys are exact genetic duplicates of him, bred entirely from his cells. He allowed me to take half a liter of his blood and a cutting of skin from his ribs. [laughs] We were in a Biblical frame of mind on the twenty-third of May 1943, at the Berghof. He had denied himself children because he knew that no son could flourish in the shadow of so godlike a father! But when he heard what was theoretically possible, that I could create one day not his son, not even a carbon-copy but another original, he was thrilled by the idea! The right Hitler for the right future! A Hitler tailor-made for the 1980s, the 1990s, 2000!
  • Proponents of human reproductive cloning do not dispute that cloning may lead to violations of clones' right to self‐determination, or that these violations could cause psychological harms. But they proceed with their endorsement of human reproductive cloning by dismissing these psychological harms, mainly in two ways. The first tactic is to point out that to commit the genetic fallacy is indeed a mistake; the second is to invoke Parfit's non‐identity problem.
  • Populations with low numbers of individuals possess minimal genetic variation. It is therefore desirable to avoid further losses of diversity. A subsequent generation resulting from natural breeding or artificial insemination (AI) would contain some, but not all, of the genetic variability of its parents. Losses would occur if any of the individuals failed to breed, a strong possibility with small populations. If cloning was guaranteed to be 100% successful, a good strategy might be to clone every individual (not impossible if the population size is only 9–18), then allow the offspring to mature and breed naturally. The probability of losing genetic diversity would then be reduced, especially if each parent gave rise to more than two identical copies of itself. Thus, an interesting and novel theoretical principle in animal conservation emerges, where individuals are effectively induced to reproduce asexually, somewhat like plants, thereby improving the long-term fitness of the species through the retention of genetic diversity.
  • Current success rates with nuclear transfer in mammals are very low (less than 0.1–5% of reconstructed embryos result in a live birth (Di Berardino 2001, Wakayama & Yanagimachi 2001). Therefore, between 20 and 1000 nuclear transfers would need to be performed to achieve one viable offspring.
  • Several attempts at cloning exotic or endangered species have received widespread publicity (e.g. Gaur (Bos gaurus), Banteng (Bos javanicus) and Bucardo (Capra pyrenaica pyrenaica)). The distinguishing feature of these examples is that they employed trans-species cloning (Fig. 2⇓). In these instances, the oocyte cytoplasm being used to create embryos was derived from common domesticated species (Bos taurus (cow) or Capra hircus (goat)), while the cell nucleus was from the species of interest. Trans-species clones inevitably differ from either of the parental species in their nucleo-cytoplasmic characteristics. At the very least, mitochondria inherited from the recipient oocyte would have a major influence over functions, such as muscle development and physiology, that depend on mitochondrial gene expression. Animals resulting from these trans-specific cloning efforts would be scientifically valuable for their insights into the functional relationships involved in nucleo-mitochondria dialogue, but would not be directly useful for supporting the endangered populations.
  • Reproductive cloning is a technology used to generate an animal that has the same nuclear DNA as another currently or previously existing animal. Dolly was created by reproductive cloning technology. In a process called "somatic cell nuclear transfer" (SCNT), scientists transfer genetic material from the nucleus of a donor adult cell to an egg whose nucleus, and thus its genetic material, has been removed. The reconstructed egg containing the DNA from a donor cell must be treated with chemicals or electric current in order to stimulate cell division. Once the cloned embryo reaches a suitable stage, it is transferred to the uterus of a female host where it continues to develop until birth.
    Dolly or any other animal created using nuclear transfer technology is not truly an identical clone of the donor animal. Only the clone's chromosomal or nuclear DNA is the same as the donor. Some of the clone's genetic materials come from the mitochondria in the cytoplasm of the enucleated egg. Mitochondria, which are organelles that serve as power sources to the cell, contain their own short segments of DNA. Acquired mutations in mitochondrial DNA are believed to play an important role in the aging process.
  • Reproductive cloning is expensive and highly inefficient. More than 90% of cloning attempts fail to produce viable offspring. More than 100 nuclear transfer procedures could be required to produce one viable clone. In addition to low success rates, cloned animals tend to have more compromised immune function and higher rates of infection, tumor growth, and other disorders.
  • In 2002, researchers at the Whitehead Institute for Biomedical Research in Cambridge, Massachusetts, reported that the genomes of cloned mice are compromised. In analyzing more than 10,000 liver and placenta cells of cloned mice, they discovered that about 4% of genes function abnormally. The abnormalities do not arise from mutations in the genes but from changes in the normal activation or expression of certain genes.
    Problems also may result from programming errors in the genetic material from a donor cell. When an embryo is created from the union of a sperm and an egg, the embryo receives copies of most genes from both parents. A process called "imprinting" chemically marks the DNA from the mother and father so that only one copy of a gene (either the maternal or paternal gene) is turned on. Defects in the genetic imprint of DNA from a single donor cell may lead to some of the developmental abnormalities of cloned embryos.
    Due to the inefficiency of animal cloning (only about 1 or 2 viable offspring for every 100 experiments) and the lack of understanding about reproductive cloning, many scientists and physicians strongly believe that it would be unethical to attempt to clone humans. Not only do most attempts to clone mammals fail, about 30% of clones born alive are affected with "large-offspring syndrome" and other debilitating conditions.
  • Human Genome Project Information, "Cloning Fact Sheet". Archived from the original on 2 May 2013. Retrieved 25 October 2011.
  • Developments in biotechnology have raised new concerns about animal welfare, as farm animals now have their genomes modified (genetically engineered) or copied (cloned) to propagate certain traits useful to agribusiness, such as meat yield or feed conversion. These animals have been found to suffer from unusually high rates of birth defects, disabilities, and premature death.
  • "Therapeutic cloning will hopefully be the solution for all the problems that have plagued transplant medicine for many years -- the shortage of tissue and rejection. Stem cells lines are basically immortal and with them we can turn them into any cell type," Robert Lanza, chief scientist for Advance Cell Technology, a U.S. company involved in regenerative medicine.
  • Helen Wallace is more skeptical and wary about the demands on women from human cloning: "Claims that you could clone individual treatments of human beings to treat common diseases like diabetes, suggests you need a huge supply of human eggs. Where are they going to come from? Even if you don't have a religious view of the sanctity of life, you have to ask is there going to be a massive trade in human eggs from poor women to rich countries."
  • For Lanza, reproductive cloning is "like sending up a rocket knowing it's got a 25 percent chance it's going to blow up -- it's just not ethical."
  • She hates her own clones. She burns her own clones. Frankly, you're a career break for the right therapist.
  • Some ethicists regard the cloning of humans as inherently evil, a morally unjustifiable intrusion into human life. Others measure the morality of any act by the intention behind it; still others are concerned primarily with the consequences-for society as well as for individuals. Father Richard McCormick, a veteran Jesuit ethicist at the University of Notre Dame, represents the hardest line: any cloning of humans is morally repugnant. A person who would want a clone of himself, says McCormick, "is overwhelmingly self-centered. One Richard McCormick is enough." But why not clone another Einstein? Once you program for producing superior beings, he says, you are into eugenics, "and eugenics of any kind is inherently discriminatory." What's wrong with duplicating a sibling whose bone marrow could save a sick child? That, he believes, is using another human being merely "as a source for replaceable organs." But why shouldn't an infertile couple resort to cloning if that is the only means of having a child? "Infertility is not an absolute evil that justifies doing any and every thing to overcome it," McCormick insists.
  • This study demonstrates, to our knowledge for the first time, that adult neurons can be cloned by nuclear transfer. Furthermore, our data imply that reduced amounts of H3K9me2 and increased histone acetylation appear to act synergistically to improve the development of cloned embryos.
  • In this series of relics, body and flesh are there to be sold as artwork, in order to overcome the taboo of selling one's own body.
The body of text, the bodies of letters: flesh is hereto be given to DNA analysis, taking the risk of being used in the future, and that a body, a replicant, a clone can be constructed.
  • Orlan, "ORLAN: A Hybrid Body of Artworks", edited by Simon Donger, Simon Shepherd p. 47.
  • Meet Bessie, who could soon be the first cow to give birth to a cloned ox.
    If she delivers the rare Asian gaur growing inside her, she will herald a stunning new way to save endangered, or even recently extinct, animals.
    The bovine surrogate mother is carrying the gaur fetus on a farm near Sioux City, Iowa, and is expected to give birth to "Noah" next month.
    "He will be the first endangered animal we send up the ramp of the ark," said Robert Lanza, the vice president of medical and scientific development at Advanced Cell Technology, and one of the lead authors of a study published Sunday in the journal Cloning. "This is no longer science fiction. It's very, very real."
  • It is also our view that there are no sound reasons for treating the early-stage human embryo or cloned human embryo as anything special, or as having moral status greater than human somatic cells in tissue culture. A blastocyst (cloned or not), because it lacks any trace of a nervous system, has no capacity for suffering or conscious experience in any form – the special properties that, in our view, spell the difference between biological tissue and a human life worthy of respect and rights. Additional biological facts suggest that a blastocyst should not be identified with a unique individual person, even if the argument that it lacks sentience is set aside. A single blastocyst may, until the primitive streak is formed at around fourteen days, split into twins; conversely, two blastocysts may fuse to form a single (chimeric) organism. Moreover, most early-stage embryos that are produced naturally (that is, through the union of egg and sperm resulting from sexual intercourse) fail to implant and are therefore wasted or destroyed.
  • SNCT is a widely used cloning technique whereby a cell nucleus containing the genetic information of the individual to be cloned is inserted into a living egg that has had its own nucleus removed. It has been used successfully in laboratory animals as well as farm animals.
    However, until now, scientists hadn't been able to overcome the limitations of SNCT that resulted in low success rates and restricted the number of times mammals could be recloned. Attempts at recloning cats, pigs and mice more than two to six times had failed.
    "One possible explanation for this limit on the number of recloning attempts is an accumulation of genetic or epigenetic abnormalities over successive generations," explains Dr. Wakayama.
  • Dr Singla added, "Without cloning, one buffalo would have given birth to a single offspring every year. Through cloning, we can get surrogate mothers to give birth to 40-50 calves every year."
  • Critics worry the cloning of endangered species could hamper efforts to conserve biodiverse habitats by offering a sort of "silver bullet" solution to saving endangered species.
  • "When you get down to a few dozen members of a species you're really talking about very serious problems," Lanza said. "So this is a tool. From now on that there's no need ever really to ever lose that genetic diversity that's remaining in these wild populations."
  • No doubt the person whose experimental skill will eventually bring forth a clonal baby will be given wide notoriety. But the child who grows up knowing that the world wants another Picasso may view his creator in a different light.
  • Drucker: You know, we shouldn't forget that not long ago, there were almost no more fish left in the ocean and half the world's population faced the threat of hunger. Cloning technology turned that around. Extremists won't admit they'd rather people went hungry than eat cloned fish, so they yell about human cloning.
Reporter: Do you think human cloning laws should be changed?
Drucker: Suppose a ten-year-old boy is in the hospital, dying of liver cancer. Thanks to Dr. Weir's work, we can save that boy. In the next bed lies another ten-year-old boy whose parents love him just as much, only he has an inoperable brain tumor. You cannot clone a brain. The only way to save him would be to clone the whole person. How do you tell that boy's parents that we can save the first boy, but the research that would have saved their son wasn't done, because of a law passed by frightened politicians a decade ago?
  • It's a different way to begin separating out nature and nurture, and to see how different this boy would be. But I have many times been asked if my children have followed me into research — it's something people subconsciously expect. For a clone, the pressure would be even greater. People would expect the clone to be like the original, and put expectations and limitations on them, and that's the reason why I don't like to use that technique. I think people should be wanted as individuals.

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