Cloning

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"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."

- Cloning

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"In response to something that Dr. Frist said, I need to object, and that is that, Senator, you insist on separating therapeutic cloning and embryonic stem cells. However, in my own case, I require re-myelination of nerves. That means replacing the conductive coat of fat, myelin, that allows electricity to come down, currents from the brain to the central nervous system for function. At the moment, only embryonic stem cells have the potential to do that, and experiments are being done now in larger animals demonstrating that. In fact, a scientist at Washington University, Dr. John McDonald, whom I have been working with says that there is no way he would inject stem cells without being able to use my own DNA for safety reasons. So without the ability to use my own DNA, without that somatic cell transfer, I am out of luck. The other thing is to please remember that therapeutic cloning, nucleus transplantation, is done with unfertilized eggs. You keep referring to destroying an embryo. I think that destroying an embryo is what happens when the leftovers from fertility clinics are thrown out. We can agree that they go to the garbage routinely. But to say that an unfertilized egg has the same status, I believe is incorrect, and I think that this is the line of research that holds so much promise and can also get us around the ethical quandary that we keep putting ourselves in. We are talking about an unfertilized egg that will never leave the lab, that will never be implanted in a womb, and that can be regulated. And it is crucial for research."

- Cloning

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"James Kelly: Complex technical obstacles stand in the way of human cloning through somatic nuclear transfer ever being medically used in humans. These obstacles include short and long term genetic mutations, tumor formation and unexpectedly tissue rejection. In addition, the cloning process is very inefficient in itself, often requiring a hundred women’s eggs to create an embryo able to yield stem cells. Because of these roadblocks, scientists expect it will take decades before cloning will have clinical uses, if ever, regardless of whether stem cells from cloning ... cloned embryos can show results in the lab. And leading scientists in the embryonic stem cell field, including James Thompson, have admitted that the cost of cloning based therapy would be astronomical. Others have simply said that no one can afford it. If human cloning research is allowed to move forward, these obstacles will need to be overcome for each of cloning's potential medical uses. This will unavoidably necessitate diverting crucial resources from other avenues that have already proven their ability to safely address the conditions that cloning has only hoped to address in the distant future. In humans, adult stem cells have successfully been used to treat multiple sclerosis, diabetes, certain forms of cancer, stroke, Parkinson's disease, and immune deficiency syndrome. They're in clinical trial for spinal cord injury, heart disease, and ALS. More work certainly needs to be done to refine and expand their uses and to improve their performance, but refining, expanding and improving are far cries from embarking on a new, highly problematic research, with little hope of leading to medically available treatments. In fact, such a trade off would be madness. Yet we're being told that cloning is our brightest hope to cure disability and disease. Many sick, disabled and dying people have embraced this message in the name of desperation and trusting hope."

- Cloning

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"Stuart Newman: I'm here to argue that not only is full term cloning a bad idea, as Dr.Jaenisch forcefully pointed out, but that so-called therapeutic cloning, that is, nuclear transfer to make stem cells, is also in the long run going to be a bad idea. And I want to emphasize that my views on this don't arise from any notion of the sanctity of the embryo or any religious ideas or anything like that. But I do feel that there's probably nobody in this room that won't have some point in which they say, this is unacceptable. So for example, if a clonal fetus is allowed to develop to seven months, in order to harvest cells, this might be unacceptable to more people than growing clonal embryos for only seven days or 14 days. Probably everybody in this room would say, we certainly don't want to make full term babies for the purpose of transplanting tissue. Probably everybody would object to that. What I would like to convey to you is that the logic of the science and medicine is leading us in that direction. Not because anybody is motivated to do that per se; specifically, I don't think any of the scientists involved are motivated to do that, but there are all sorts of pressures, patient pressures, commercial pressures--and the patient pressures I believe are very genuine, authentic and must be satisfied in some way, so I'm not arguing that there shouldn't be patient pressures--but there will be pressures to bring us to the point. As was quoted from my Senate testimony, there are, in fact, stem cells that can be harvested from two month old embryos. These are called “embryo germ cells.” So if clonal embryos were produced, and it became possible, as some scientists are attempting, to grow the embryo for two months rather than just for seven days or 14 days, it would be possible to harvest these embryo germ cells. Now, why would you want to do that? John Gearhart at Johns Hopkins has worked on those cells, and has shown that they are apparently as versatile as embryo stem cells from the early petri dish cultures, but they don't have the same propensity to cause cancer when transplanted into adult animals. Now that's a very important motivation for harvesting these later stem cells."

- Cloning

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"Stuart Newman: Dr. Jaenisch mentioned the scenario of treating diabetics with embryo stem cells. But one of the problems in Type 1 diabetics is that they reject their own insulin producing cells. So even if you could clone that person into a clonal embryo, grow up islet cells and transplant them back into the diabetic, the person's immune system would still reject those cells. So you would have to find some way to immune-suppress the diabetic patients anyway, so as to treat them with embryo stem cells. I think that the American people are very optimistic and only want to hear about the promises, and don't want to hear about the downside. I just point out that in a very recent paper of Dr. Jaenisch 's that he spoke about, where he showed the proof of principle of using stem cells and transplanting differentiated bone marrow cells back into the mouse with the immune deficiency, there was another experiment as well where they corrected the genetic defect in the embryo stem cells. The embryo stem cells were used to produce a full term clone of the original genetically defective mouse, but with the genetic condition corrected. They now had a genetic twin of the original mouse with the corrected gene, and were then able to use bone marrow from that corrected mouse to treat the original mice. Now here's a scenario for which many people would say, “great!” People are already having new children to provide bone marrow for children with genetic conditions. If the public was aware that now you could clone your sick child and use the bone marrow from the new child--whom you'll love like your old child, of course--and transfer that bone marrow back into your sick child, huge sectors of the public would find that acceptable. And this is what I mean when I say that we're on a track where we're coming closer and closer to full term cloning, by way of all sorts of intermediate stages. And it's not that there aren't people already advocating this."

- Cloning

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"Christopher Reeve: I work with Dr. John McDonald at Washington University in St. Louis, and he is a very knowledgeable researcher on (Inaudible) stem cells, and a few years ago he said to me that in order to cure my particular condition, which is demyelination of nerves in a very small area of the spinal cord, right at the second cervical vertebrae, that if you imagine the rubber coating around a wire that allows conductivity of electricity, the same thing as with nerves, myelin is like that rubber coating. It's a fatty substance that if it comes off of the nerves, then signals do not go from the brain down to the spinal cord as required. However, it is possible, and he's demonstrated this as graphic(?) as possible, to re-myelinate. Now, a few years ago, he said, we would be willing to inject human embryonic stem cells into you and hope for the best. But hoping for the best is a very dangerous proposition for people with spinal cord injuries because our spinal cord injury affects every organ in the body, and the most serious side effect is that it severely compromises the immune system, so spinal cords patients, particularly with high level injuries like mine, are prone first to pneumonia, which I've had at least five times since my injury, many patients often die from that. Also, it compromises the cardiovascular system, compromises the digestive tract, the ... your whole bowel-bladder-sexual function, skin integrity and also bone density, so that osteoporosis becomes a very ... a very critical factor. So literally he said to me that the immunosuppression that would be required just to inject 30million human embryonic stem cells from an anonymous donor might kill me. And now, he would be unwilling as a doctor, because of the ethics involved that a doctor is ethically bound to give his patients the best possible treatment, he would not inject me with embryonic stemcells unless we go the other route, which is therapeutic cloning- taking an egg, removing the nucleus, taking DNA from my skin and deriving stem cells from that, which would be injected in a manner that would probably not be rejected by my immune system. So my future, and others would agree, many scientists would agree, my future, in terms of being able to recover will depend on some way of delivering stem cells without compromising my immune system and therapeutic cloning, which would use my DNA is the best hope."

- Cloning

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"Christopher Reeve: No, you have to understand that therapeutic cloning is a very nascent technology that's not ready for use in humans. But knowing that it will not . . . provided our scientists are allowed to go ahead with the research, it really shouldn't take that long before they're ready for humans. However, knowing that there is a better technology out there than just using embryonic stemcells, he as a doctor feels, given the immune rejection problem for people with spinal cord injuries, he's not going to go ahead, as he had planned to. There was a plan to actually use embryonic stem cells as soon as it would be allowed by the FDA. He is not going to do that until therapeutic cloning gets to the point where it could be applied to humans. And I just want to make one other very quick comment and that is in England, just a month ago, Dr. Ann Bishop, who works with the tissue engineering corporation over there, was able to take mouse embryonic stem cells that derived . . . had been made obviously therapeutic cloning, and they turned those cells into tissue that is applied to the lungs, to deficient cell types or cell tissues in the lungs, and said, have already reported, I guess it's public knowledge, that they feel they are now ready to do it in humans, so the idea that it would be decades before you could get to human application, I think that is one example I'm giving you right now of the fact that that's not true. I can give you another example. Doctor Oswald Stewart, of the Reeve Research Center, UC Irvine has said that you could probably get to the use of therapeutic cloning in humans within about three to five years. So I absolutely dispute the time line that's been put up before."

- Cloning

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"James Kelly: This is a topic that I discussed with Dr. Young of Rutgers. Dr. Young is in favor of therapeutic cloning, and he pointed out to me on the Internet, his Internet forum, speaking on the moral issues, he said that why ban cloning in the United States when somebody might be able to get on a plane, fly to England, whatever, if it was available, if it was a treatment, and be cloned? The only way we could find out whether or not they actually had such a therapy upon their return would be to do a DNA check of all returning people to the United States, which is ... of course is not going to happen. My response to Dr. Young and here again, my reasons for even looking into this in the first place and for opposing cloning on the scientific reasons I've mentioned in my opening five minutes, my response to Dr. Young is, people can get on a plane, and they can fly to other countries. NBC mentioned the Eastern European countries as one where they might be able to engage in child prostitution. Does that mean that we should make child prostitution legal in the United States? Because if cloning is going to be banned, it's going to be banned because of these scientific reasons. It's going to be banned for moral reasons. That's why the ... that's why Senator Brownback proposed the legislation. And if it's banned for moral reasons, we shouldn't change our moral perspective in the United States simply because somebody else somewhere else in the world says something is moral that we in the United States have decided is immoral."

- Cloning

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