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Lab-grown brain cells should aid research into Alzheimer's

Fergus Walsh | 14:12 UK time, Friday, 4 March 2011


Scientists in the United States have managed to turn human embryonic stem cells into a type of brain cell linked to memory loss in Alzheimer's disease. The research, published in the journal Stem Cells, should help in the development and testing of potential new medicines to treat the neurodegenerative disease which affects around half a million people in the UK.

The researchers at Northwestern University in Chicago managed to coax the stem cells into becoming a type of neuron which dies off early in people with Alzheimer's disease. The cells in question are basal forebrain cholinergic neurons (BFCN), which have a key role in memory function, and their loss is thought to be significant in the early stages of the neurodegenerative condition.

These dishes of cells should provide a near limitless supply of neurons for research. Scientists need to know why these cells - critical for memory function - fail in Alzheimer's disease. It should enable them to test compounds on the laboratory samples in the search for treatments.

One of the authors of the study, John Kessler, chair of neurology at Northwestern University said: "We can literally screen tens of thousands of drugs at a time to find the kind of compound that will keep these cells alive. We can ultimately think about transplanting the cells to help the memory deficit." He said his team had also created the neurons from the skin cells of Alzheimer's patients and from healthy volunteers. He was cautious about when the research might yield treatments but said 10 years appeared "realistic".

The Alzheimer's Society said the study was a "major step forward" but went on to say that further research was needed to find out whether these stem cells actually work in the brain. It urged greater investment in dementia research. The term "major breakthrough" was used on the Today programme on BBC Radio 4 although it was made crystal clear that benefits for patients were a long way off.

Another charity, Alzheimer's Research UK was more cautious. It said the prospect of stem cells being used as a treatment for the disease was still a very long way off and there was no evidence yet to suggest this method would be able to help people with dementia.

I confess I worry about the phrases "major breakthrough" and "major step forward". For me, the former should be reserved for something which is a game-changing piece of research, or a new device or treatment which transforms the way we combat a condition. Like many things it's hard to describe, but you know it when you see it. "Major step forward" is problematic unless you also know how many steps there are left to travel on a journey.

It seems to me that this research is another tantalising example of what MIGHT ultimately be achieved through manipulating human embryonic stem cells - the body's master cells.

Being able to generate the neurons which fail in early Alzheimer's and to test agents on them that may promote survival, will be extremely useful. But families affects by Alzheimer's need to know that there are a whole lot of major steps forward still needed before it yields an effective treatment for the disease.


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  • 1. At 3:28pm on 04 Mar 2011, John_from_Hendon wrote:

    Fergus wrote: "I confess I worry about the phrases "major breakthrough" and "major step forward"

    And quite right to do so.

    Interesting that you felt it was right and proper to write about one of the debilitating illnesses of old age when you managed not to see the story on the inadequate care of the elderly near death on 15th Feb! Is it perhaps that you see dementia as in some way curable whereas death is not? But Fergus, both you and I, will die and I don't know about you but I would prefer not to do so in too much unnecessary discomfort and pain.

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  • 2. At 7:07pm on 04 Mar 2011, Grey Animal wrote:

    In some ways, this really is a "major breakthrough" and a "major step forward" - it certainly is so from the scientific and technical point of view, though not necessarily from the clinical, which I suspect is what most of the general public are concerned with. Cell culture and induction of differentiation are always a bit of a black art, and any development which makes culturing a new cell type possible is a very significant development.

    It is, however, almost certainly going to be a long, slow path from the ability to culture unlimited quantities of BFC neurons to any improved treatment for AD and other neurological disorders that affect these cells, whether it's by the introduction of new drugs or - more speculatively - by cell implantation. It's a very rare treatment indeed which is so evidently effective and safe that its introduction can be fast-tracked; giving a horizon for improved treatments stemming from this discovery of a decade is, I think, very optimistic. However, there is nothing wrong with cautious and informed optimism, particularly when considering such a distressing and prevalent condition. The researchers concerned deserve our plaudits.

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  • 3. At 7:09pm on 04 Mar 2011, ThatWasKrul wrote:

    1. At 3:28pm on 04 Mar 2011, John_from_Hendon wrote:

    What a rude and pointless comment. This blog post was about recent medical research into Alzheimer's disease, not care for elderly dementia patients.

    Nowhere does the author say that they would be opposed to better care for those suffering from dementia, in fact I think they would probably welcome it. But it has nothing to do whatsoever with the topic at hand and that's why they didn't mention it.



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  • 4. At 7:11pm on 04 Mar 2011, mscracker wrote:

    Not even a mention of ethical queasiness re. creating human life just to destroy it?

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  • 5. At 8:01pm on 04 Mar 2011, Paul_of_Surrey wrote:

    Often I suspect that institutions publish press releases on recent research to get publicity which will help with obtaining or retaining funding.
    Much of what is reported (whether in physical sciences or medicine) seems to be simplistically described and over-hyped. Recent reports on "tractor beams" are an example of something which will probably never have a practical application.
    The research described above does seem a long way from anything which can help sufferers from dementia.
    The primary beneficiaries of the research, for the time being, will be those who obtain salaries and bonuses from publishing (and/or patenting) research and obtaining further grants.

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  • 6. At 8:01pm on 04 Mar 2011, John_from_Hendon wrote:

    #3. ThatWasKrul wrote:

    #1. John_from_Hendon wrote:

    "What a rude and pointless comment. This blog post was about recent medical research into Alzheimer's disease, not care for elderly dementia patients."

    Watching and being helpless at die is the end for many dementia patients. Fergus did not choose to blog about near death care a while back and he still avoids the subject. So I completely reject your criticism of my response. If you are unable to accept that death is the part of healthcare perhaps one day you will be surprised, but then you will find that you are unable to blog about what is happening to you and deeply regret not making more of a fuss while you were still capable!

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  • 7. At 8:30pm on 04 Mar 2011, dramaqueen wrote:

    #4. wrote: Not even a mention of ethical queasiness re. creating human life just to destroy it?

    Embryonic stem cells come from embryos that are surplus from IVF treatment. They are not simply embryos created especially for research, and they must be used within 14 days. For me, there is no ethical issue surrounding their use in medical research. Many parents do not want to donate their embryos to other couples, and the only other alternatives for them are to throw them away as rubbish, or to freeze them. Either way, my own personal reaction is that this shows a higher regard for the embryo, which is 16 cells, smaller than a pin head, than treating them as though they were nothing.

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  • 8. At 8:42pm on 04 Mar 2011, Krzysztof Wasilewski wrote:

    In some parallel way there should be a research in creating a computer equivalent to the human brain. I think that in the future we'll have digitized copies of our brains downloaded into computers when we are still in our twenties. Such copies could be used in medical treatment, when the need arises, especially in our old age.

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  • 9. At 8:56pm on 04 Mar 2011, Bradfordbelle wrote:

    Scientific research and progress is to be applauded by all means. What still worries me is the massive increase in world polulation, and the increasing percentage of elderly people that the World is having to support and care for. No where near enough endevour or resources is being put into solving these problems. We just continue to bury our heads in the sand! With the horrendous rate of inflation, that poor governance is mainly responsible, a very small percentage of the elderly can honestly afford their old age, especially with expensive ailments that many of our eldely suffer.

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  • 10. At 9:05pm on 04 Mar 2011, Grey Animal wrote:

    John_from_Hendon wrote:
    Fergus did not choose to blog about near death care a while back and he still avoids the subject.

    Fergus isn't obliged to write about something simply because it interests you, and it is rude of you to say that he is avoiding doing so. Please remember that this is Fergus's space, and that we are guests here!

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  • 11. At 10:21pm on 04 Mar 2011, Joe Roberts wrote:

    Research for an Alzheimer's preventive is critical in the United States because of the economic burden faced by
    Medicare and patients' families. Diagnostic measures don't help right now except to give patients and their families more time to make custodial care arrangements.

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  • 12. At 10:49pm on 04 Mar 2011, John_from_Hendon wrote:

    #10. Grey Animal wrote:

    "John_from_Hendon wrote:
    Fergus did not choose to blog about near death care a while back and he still avoids the subject.

    Fergus isn't obliged to write about something simply because it interests you, and it is rude of you to say that he is avoiding doing so. Please remember that this is Fergus's space, and that we are guests here!"

    And you should remember that this is a blog where Fergus chooses to write about what he chooses, and if we consider that he should be looking at something critical to everyone (we are all going to die) then perhaps to keep silent betrays everyone. To ignore death, particularly when there was so much news coverage of the poor way that it is handled in our hospitals can't be done after we have experienced it, so we must raise the issue and discuss it now, before we die.

    Fergus has not written about death at all since I have been reading his blogs and thus, as the topic is raised, from time to time I think it is accurate to note that he has avoided the topic. He was happy enough to write about bird flu when there was the 'prospect' of millions of dead but he did not choose to write about the recent report about the care of the dying in hospital. I see this as avoiding the issue.

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  • 13. At 11:35pm on 04 Mar 2011, Tom Ainscough wrote:

    Personally I think people are actually missing the key point of this. The important point isn't that there a possibility that in the very distant future it may be possible to use stem cells to replace those neurons lost through Alzheimer's, this is still a pipe dream, and although the idea is appealing it isn't going to happen for a very long time yet. Furthermore, even if the technology is eventually developed, it may well never be cost effective enough to help a significant amount of people, and may instead only serve to only exacerbate the current situation of very few people actually being able to afford to care for those with Alzheimer's.

    What is truly amazing however is that one of the major obstacles standing in the way of a cure for being Alzheimer's may well be very close to being overcome. The issue with the study of Alzheimer's is that gaining consent to open up the skulls of those suffering from the disease is a little hard to come by, and without being able to do this, progress towards a cure is understandably slow as a true understanding of the disease cannot be gained.

    Similarly, testing new drugs is also incredibly hard to gain consent for when its people you are dealing people, but what this technology will allow researchers to do is to test any drugs they want whenever they want and however they want, without risking the well being of any Alzheimer's patients. I personally believe that it is self evident that this will speed up the discovery of a cure for Alzheimer's.

    No matter what people say, anything that brings us even one step closer to curing this disease that affects such a huge number of people world wide, is without doubt a major break through. No matter how many more steps there may yet be left to take before a cure is ultimately discovered, as every step on the path is just as important as the final destination itself.

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  • 14. At 11:49pm on 04 Mar 2011, Penny1988 wrote:

    My mother has suffered from this terrible disease since I was 12 years old.... and I see this as a major breakthrough - not because it actually is a major breakthrough but because reporting on Alzheimer's is few and far between - so frankly any reporting on the subject will get my vote so I thank Fergus for bringing this to my attention.

    Unfortunately Alzheimer's does not get enough funding from the UK government because it is often pushed aside as an 'old persons disease’ people who are old and dying anyway - cancer gets far more funding which is understandable as it affects more people however diagnosis of Alzheimer's is on the increase and currently the government only spend £11 per head on research for Alzheimer's unlike cancer which gets £22.

    I do feel that if Alzheimer's had had more funding from the start then we would be much closer to understanding the disease now and 'break throughs’' could occur more often.

    Also just to agree with . Grey Animal - this is an article about dementia which is actually almost 80% of the reason why the elderly are in a care home - prevention is better than cure and this is an article about brand new information regarding that illness - it is well known and in the public domain that care homes are often quite the opposite - many are cared for very badly ( there have been reports of many incidents such as the 15th Feb.) - which is therefore nothing new to report is it? Developments on an irreversible illness that affects half a million people which there is absolutely no cure for is something new - which is probably the reasoning behind Fergus reporting this as oppose to the 15th Feb. incident.

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  • 15. At 11:51pm on 04 Mar 2011, Penny1988 wrote:

    here here Tom Ainscough! I totally agree

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  • 16. At 01:12am on 05 Mar 2011, Piggyback wrote:

    I have been hearing about breakthroughs for Alzheimer's for the past decade.

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  • 17. At 12:54pm on 05 Mar 2011, Tom Ainscough wrote:

    And you probably will be for another decade yet, but that doesn't mean that a cure won't eventually be found... if you had any idea of how complex this problem really is you wouldn't be so disparaging

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  • 18. At 1:03pm on 05 Mar 2011, donscott wrote:

    How incredibly judgmental of you John_from_Hendon. You have absolutely no idea why Fergus hasn't written about the topic and are being led by your assumption that he is avoiding the topic. Yes we all die, but more importantly we all live and I personally feel that is largely what these files should cover.
    It is interesting to note another occurence which humans all share and yet is barely covered in these files is birth, yet you seem to avoid complaining about that. I wonder why that is?

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  • 19. At 5:05pm on 05 Mar 2011, Nick Gotts wrote:

    "Often I suspect that institutions publish press releases on recent research to get publicity which will help with obtaining or retaining funding." - Paul from Surrey

    Well, yes, and that's obviously wrong, isn't it? An organisation publicising its successes in hope of getting the money to continue what it does well.

    "The primary beneficiaries of the research, for the time being, will be those who obtain salaries and bonuses from publishing (and/or patenting) research and obtaining further grants."

    Tut, tut. These selfish scientists, wanting to be paid for their work and rewarded for success. Disgraceful.

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  • 20. At 11:52pm on 06 Mar 2011, John Ellis wrote:

    16. At 01:12am on 05 Mar 2011, Piggyback wrote:
    I have been hearing about breakthroughs for Alzheimer's for the past decade.

    this isn't a break through this is the begining of a major revolution in technology.
    http://www.med.nyu.edu/biosketch/nixonr01

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  • 21. At 10:51am on 07 Mar 2011, Jaytack wrote:

    A recent Meta study in the USA and Germany examined 100+ studies relevant to Alzheimer's. Their conclusion was that Mercury is the most probable cause of the disease and the source of the mercury is most probably the silver coloured mercury fillings dentists put in our teeth.

    The University of Calgary in Canada has a video on its website showing the effect of mercury on brain neurons and it can be viewed at http://commons.ucalgary.ca/mercury/ The experiment was repeated with many other substances including aluminum and only mercury caused the neurons to die.

    JJ

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  • 22. At 5:47pm on 07 Mar 2011, mscracker wrote:

    @7. dramaqueen:
    I keep hearing the defense that embryonic stem cell research is ethical in that it only makes use of human life that would be otherwise discarded.The destruction of embryos intended for reproductive use is still a violation of the sanctity of human life. But they are not the only embryos that can be used in stem cell research.
    This is from: Genome.gov re. stem cells created through "therapeutic cloning:
    "In the 1998 reports, ES cells were derived from in vitro embryos six to seven days old destined to be discarded by couples undergoing infertility treatments, and embryonic germ (EG) cells were obtained from cadaveric fetal tissue following elective abortion. A third report, appearing in the New York Times, claimed that a Massachusetts biotechnology company had fused a human cell with an enucleated cow egg, creating a hybrid clone that failed to progress beyond an early stage of development. This announcement served as a reminder that ES cells also could be derived from embryos created through somatic cell nuclear transfer, or cloning. In fact, several scientists believed that deriving ES cells in this manner is the most promising approach to developing treatments because the condition of in vitro fertilization (IVF) embryos stored over time is questionable and this type of cloning could overcome graft-host responses if resulting therapies were developed from the recipient's own DNA."Kathi E. Hanna, M.S., Ph.D., Science and Health Policy Consultant-The National Human Genome Research Institute (USA)


    If I were a scientist & not "ethically queasy" about destroying a developing human life, why would I bother with embryonic materials that have been stored for long periods of time?

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  • 23. At 9:42pm on 07 Mar 2011, dramaqueen wrote:

    @mscracker: By saying "If I were a scientist & not "ethically queasy" about destroying a developing human life, why would I bother with embryonic materials that have been stored for long periods of time?" it would appear that you were suggesting that "scientists" have no regard for a developing human life - in fact, we do. We have the highest regard for it. Why not use embryos that will be discarded anyway to try and improve the quality of others' lives? Many couples do not want to donate their embryos which are surplus from IVF to other couples - that is the fundemental point. Why should we throw away or freeze embryos (not to use them - as I stated in my last post, they can only be used within a relatively short period of time) when we can show respect to our fellows AND to the "developing human life" by doing research into their potential uses?
    You state that if you were a scientist, then you would not bother with using embryonic materials - I presume you would be OK with using a hybrid embryo. Which is more "ethically correct" - to create a hybrid, or to use one that's fully human? I would go with the latter.
    I will also put forward that eventually, the use of embryonic stem cells will fade as the potential stem cells to be used in cures for humiliating diseases such as Parkinson's, Alzheimers, strokes, MS and many, many others are those found in bone marrow, thereby removing the risk of tissue rejection. I know many people affected by diseases such as these and I would want them to have a higher quality of life compared to that which they currently have.
    As a prospective medical student, I have a very high regard for human life, which is why I fully support the research being done into stem cells and, as I have already mentioned, I believe this research shows more respect towards developing human life than discarding these precious balls of cells which could mean lives changed and terminal diseases curable.
    I hope that makes sense, and that I haven't offended you too much! I just vehemently believe that we need to do something about the dieseases which tear so many lives to shreds.

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  • 24. At 10:27pm on 07 Mar 2011, mscracker wrote:

    @ 23.dramaqueen:
    No, you certainly haven't offended me & I wish you the very best of luck if you decide pursue a medical career. And my hope is, too, that the use of embryonic stem cells will fade away.
    What I tried to say is that if I were a scientist without ethical taboos regarding the destruction of a developing human life, I would seek embryonic materials that would have the best potential outcome for success in my research.Those that have been stored for a longer period of time would not be my first choice.
    But to answer your question, no, I personally speaking wouldn't be OK with using any human embryos, cloned or otherwise.

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  • 25. At 8:15pm on 08 Mar 2011, rema1 wrote:

    @ 7. Drama queen
    Its not the embryo thats actually used, its the preembryo that is, that is the group of cells up to the 14 day stage before the apprearance of a primative streak as you were saying, at this point it is no longer legal and the preembryo must be destroyed. Just thought that might be of interest to you as a perspective medic.

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  • 26. At 06:05am on 09 Mar 2011, suvivorStar wrote:

    Thank you, thank you. Any hope you can give for a family of 8 with Alzheimer's is a true blessing. Please don't give up the fight. I lost my mother, the earliest recorded case, now I am that age and living day by day.

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  • 27. At 10:49am on 09 Mar 2011, Odicean wrote:

    I'm all for relieving suffering by the use of embryonic stem cells or any other sort of stem cells. But why have scientists got into the habit of beginning every explanation of a procedure with the word 'SO'...? It is becoming as ubiquitous as the Aussie sportsman beginning every wretched answer to a question with the word 'LOOK'...
    It really is appalling.

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  • 28. At 5:58pm on 09 Mar 2011, mscracker wrote:

    25.rema1:
    "Pre-embryo" is a recent verbal construct that seeks to legitimize embryonic stem cell & human cloning research.
    It's still a human embryo, verbal acrobatics or not.

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  • 29. At 9:47pm on 09 Mar 2011, dramaqueen wrote:

    @mscracker: Thank you for your clarifications! However, I would ask how, without the use of embryonic stem cells, we can research into cures for these diseases? I don't believe it's possible, until we fully discover the how to unlock the potential of stem cells found in bone marrow.Also, after a certain period of time, embryos are no longer viable - that is, they wouldn't survive after implantation. So the alternative is to throw them away. What are your views on this? What should we do with our surplus embryos? From what you say, I infer that you have a high regard for human life, but without this much needed research we cannot cure diseases that are currently incurable eg. Parkinson's, which my Grandad is affected by, and for him, it's humiliating. Unfortunately, we're still a long way off, but thank you for your best wishes!!

    @rema1: It's still technically an embryo. It's not so much that it's illegal, it's just that the cells are too differentiated to be used. Their "totipotency" (ie. ability to develop into any type of cell when supplied with the correct hormone/other chemical) disappears after the 16-cell stage. I knew they couldn't be used after 14 days in Germany, I presumed it to be the same here. They even have to import them to Germany!

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  • 30. At 9:05pm on 10 Mar 2011, rema1 wrote:

    @dramaqueen

    A preembryo will become an embryo but they aren't classified as being the same, the primitive streak is the cut of point because this is when it becomes 'individual' in the sense that it will begin to form major structures such as the GI tract and the spinal column. I know that their totipotency is impaired in vitro at this point but it is also this point where it becomes illegal, not where they become useless for every potential topic of research. I don't know what its like in Germany as I'm only in the scientific field here.

    --

    As much as I work with in vitro preps which may make me bias and this is the foundation on which in vivo experimentation is predicted and hypothesised, I think the preembryo has a lot of misconception surrounding it, its a slippery slope but the holy grail of a cure for many diseases relies on preembryo research. Many of the experiments conducted in concentration camps in the second world war were horrific and should never be repeated (not that I'm condoning them being done in the first place) but they are still the basis of medical knowledge about some diseases. Is this not a better way to test hypothesies? The preembryo can't interpret pain until at least week 12 (although debateable)as this is when the cerebral cortex begins to form, this is rather distant from the period of less than 14 days.

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  • 31. At 3:50pm on 11 Mar 2011, mscracker wrote:

    @29. dramaqueen:
    I wish I had an immediate answer but believe, from what I've read, the use of a patient's own cells is probably the best solution for the future, both ethically & medically in regards to issues of rejection.
    I'm so sorry for your grandfather's illness.God bless him, & very best wishes for your medical future.

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  • 32. At 01:37am on 13 Mar 2011, rema1 wrote:

    @ 28. mscracker

    As before, a preembryo is a scientific classification, not just as you say ''verbal acrobatics''.
    Grouping stem cell research and human cloning is a sweeping generalisation, finding the proteome of a given pathology is a totally different scientific process to cloning a human and a totally different ethical debate.
    If preembryos weren't the best model avalible they wouldn't be used but is there really another way to model the behaviour of early pathology than to use the preembryo itself to understand its proteome from its genome? Using a patient's self cells in theory and in practice are very different things.
    If someone with a debilatating illness such as Parkinson's or a lethal disease like Alzheimer's is it right to deny them potential treatment for the sake of looking at a preembryo which feels no pain and has no awareness and does that make the price of a developed human life equal to that of a potential human who woudln't be born anyway? If a cure were avalible from preemrbyo research for one of these diseases and you felt it had been ''legitimized'' does that mean that you wouldn't take it if you needed it?
    The scientific community doesn't act to push science forward in a way that ''legitimizes'' by using ''acrobats'', it pushes science forward for the health of communities, if it didn't there would be no market for their drugs, you make it seem like research scientists are evil people for trying to cover things up by acrobating around them.

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  • 33. At 01:50am on 13 Mar 2011, rema1 wrote:

    @ 22. mscracker

    That article is cited 1998! - 13 years may not seem a lot but in science its a long time, much more recent articles have been published on this topic - something ''questionable'' in '98 may not be quite so questionable now...

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  • 34. At 1:45pm on 14 Mar 2011, mscracker wrote:

    @33:
    I don't think time changes ethics.If something was ethically/morally objectionable a dozen years ago it remains the wrong thing to do.
    I don't have a great deal of time to search online for the most recent articles on the subject & chose "genome.gov" simply because it's a government sponsored site & not associated with any religious or social institution.I found this info at that site today:

    "Therapeutic cloning, also called "embryo cloning," is the production of human embryos for use in research. The goal of this process is not to create cloned human beings, but rather to harvest stem cells that can be used to study human development and to treat disease. Stem cells are important to biomedical researchers because they can be used to generate virtually any type of specialized cell in the human body. Stem cells are extracted from the egg after it has divided for 5 days. The egg at this stage of development is called a blastocyst. The extraction process destroys the embryo, which raises a variety of ethical concerns. Many researchers hope that one day stem cells can be used to serve as replacement cells to treat heart disease, Alzheimer's, cancer, and other diseases. See more on the potential use of cloning in organ transplants.

    In November 2001, scientists from Advanced Cell Technologies (ACT), a biotechnology company in Massachusetts, announced that they had cloned the first human embryos for the purpose of advancing therapeutic research. To do this, they collected eggs from women's ovaries and then removed the genetic material from these eggs with a needle less than 2/10,000th of an inch wide. A skin cell was inserted inside the enucleated egg to serve as a new nucleus. The egg began to divide after it was stimulated with a chemical called ionomycin. The results were limited in success. Although this process was carried out with eight eggs, only three began dividing, and only one was able to divide into six cells before stopping."

    Perhaps they need to cite more recent research & you have a good point on that.But my guess is that "therapeutic cloning" is active today in labs & there are probably a variety of privately funded research projects that would be quite offensive to the sanctity of human life.We tend not to hear about them because they do not involve public funds.
    And I think "funding" is a major issue in this debate.Money can certainly influence ethical objections.Scientists are not evil people but they are human.And part of our human condition is to look the other way at something morally questionable if we can profit from it-in any way.

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