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stem cells 101

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Darkhawk28

Diamond Member
Dec 22, 2000
6,759
0
0
Originally posted by: CycloWizard
<blockquote>quote:
<hr><i>Originally posted by: <b>Vadatajs</b></i>
<blockquote>quote:
<hr><i>Originally posted by: <b>CycloWizard</b></i>
None of the embryos are aborted. Further, the embryo is still human, by definition. It has human DNA, therefore it will grow into human tissue and is therefore human life. This isn't really biologically questionable.<hr></blockquote>

Scrape the inside of your cheek with your fingernail and then wipe it on your shirt.

You've just perfomed the equivalent "destruction of human life" that stem cell research involves.<hr></blockquote>

Unfortunately, it's not that simple. If it were, then various states and the federal government wouldn't hold debates on the ethics of the situation.

<blockquote>quote:
<hr>The Council on Bioethics, appointed by President Bush as part of his stem cell research funding decision last August, issued its cloning report on July 11, 2002. The 18-member panel was unanimous in its opposition to reproductive cloning, but split on somatic cell nuclear transfer (SCNT) research (or therapeutic cloning). The panel mustered 10 votes in favor of a four-year moratorium on such research. Seven members of the panel recommended allowing SCNT research to go forward and one member abstained from making any recommendation. <hr></blockquote>
Source: [l]http://www.aamc.org/advocacy/library/research/res0003.htm[/l]
There are too many issues involved to discuss them all here, unfortunately, and obviously the jury is still out, even on this 'non-fertilization' procedure.

Yes, I've read that quote before in my research. I think they put the moratorium on the research because of the public's misconceptions of the research, thus making future research in possible jeopardy. They weren't doubting the validity of the research, just the timing.
 

CycloWizard

Lifer
Sep 10, 2001
12,348
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There's nothing valid about the research yet, as far as medical cures or treatments are concerned. They just realized that they can create some sort of stem cells. Ethics councils don't base decisions based on the public's misconceptions, but rather on the ethical implications.
 

Vadatajs

Diamond Member
Aug 28, 2001
3,475
0
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Cyclowizard:

It is that simple; it is ignorance of the process that drives the ethics debates. And ethics implications are partially (mostly actually, based on mores that vary significantly from culture to culture) a function of public misconceptions. When you look back over history, at monsters like Mengele, the Stanford prison experiment, and the Milgram experiment; valuable lessons were learned by means that were unethical by conventional morality (of the three, Mengele's research is probably the most valuable when it comes to testing the limits of human endurance and the like).

Also the slippery-slope (Bush's words, not mine) connection between stem-cell research and human cloning is just that; a slippery-slope fallacy.
 

Darkhawk28

Diamond Member
Dec 22, 2000
6,759
0
0
Originally posted by: CycloWizard
There's nothing valid about the research yet, as far as medical cures or treatments are concerned. They just realized that they can create some sort of stem cells. Ethics councils don't base decisions based on the public's misconceptions, but rather on the ethical implications.


Sure they do, if the public isn't properly educated on the matter, any decision rendered could lead to a public outcry. I think they accepted the moratorium to prevent a illconceived public ostrocizing and to give them some time to further the public's awareness of the advancement of the research. Although I'd imagine they did this kicking and screaming. LOL


Also, this self-imposed moratorium also precluded any congressional involvement. They did this because they feared an all-out ban on SCNT. It was, in my opinion, an investment in time so they could garner more public and political favor toward the research. Plus, you have to understand is that the council that proposed the moratorium was appointed by the Bush administration who has to (on the surface at best and religiously against it at the least) be against stem cell research. (*** Please note: This is not a flame at President Bush. Just a statement of fact on this subject. Thank you. ***)

Trust me, I will wholeheartedly agree that we need to proceed very carefully, but we need to proceed and proceed NOW.
 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
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Originally posted by: Vadatajs
Cyclowizard:

It is that simple; it is ignorance of the process that drives the ethics debates. And ethics implications are partially (mostly actually, based on mores that vary significantly from culture to culture) a function of public misconceptions. When you look back over history, at monsters like Mengele, the Stanford prison experiment, and the Milgram experiment; valuable lessons were learned by means that were unethical by conventional morality (of the three, Mengele's research is probably the most valuable when it comes to testing the limits of human endurance and the like).

Also the slippery-slope (Bush's words, not mine) connection between stem-cell research and human cloning is just that; a slippery-slope fallacy.

You're arguing away ethics by saying that ethical considerations are a matter of public misconception? Can you tell me why I attended, not more than a year ago, a conference on the ethical considerations on human cloning and stem cell research? The committee of this conference was made up entirely of engineers with both PhD and MD degrees who specialize in biomedical engineering, tissue engineering, and cloning/stem cell related research. Are you inferring that THEY have misconceptions about the issues? I would consider them the experts in the field. Even this committee could not come to a consensus on the issues, so I strongly doubt that it is that simple. I'll see if I can track down the minutes for the conference (unfortunately, I didn't have $100 at the time for the CD copy :p).

Further, your inferrence that unethical behavior is ok, as long as we get useful results in the end (the end justifies the means) is very disturbing.
 

Darkhawk28

Diamond Member
Dec 22, 2000
6,759
0
0
Cyclowizard,

In order to prevent a congressional ban on stem cell research, they accepted the four year funding moratorium in the hopes that in four years attitudes would be different and public awareness would be greater. The researchers don't feel therapeutic cloning is unethical, just reproductive cloning. The general public and members of Congress, by in-large, don't understand the difference between the two and most people can't get passed the "baby-killing" mentality toward the research.

With the research receiving such angst by the public and members of congress, they accepted the commission's proposal of a funding moratorium. Even the split in the President's commission was pretty close (which to me says something) with this ....

"There is no legislation pending in Congress to impose a moratorium on SCNT research. On July 12, 2002 Dr. Maxine Singer, President of the Carnegie Institution, presented the Council on Bioethics with a petition against a moratorium and a ban on SCNT. Over 2,000 medical schools and university science department faculty members signed the petition.. "The petition signals that a large group of informed medical and scientific opinion in this country does not agree with the Council's call for a moratorium," said Dr. Singer. "The petition amounts to an urgent request to allow this promising research to go forward in the interest of millions who are afflicted with severe childhood and adult illnesses." The Council for the Advancement of Medical Research organized the petition. "

They don't want a Senator Brownback trying to completely banning all of their research, so the council accepted the moratorium. It's the misconceptions like Brownback has that threatens the development of the research permanently. They want to take this time to make people more educated on SCNT.
 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
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Originally posted by: Darkhawk28
Cyclowizard,

In order to prevent a congressional ban on stem cell research, they accepted the four year funding moratorium in the hopes that in four years attitudes would be different and public awareness would be greater. The researchers don't feel therapeutic cloning is unethical, just reproductive cloning. The general public and members of Congress, by in-large, don't understand the difference between the two and most people can't get passed the "baby-killing" mentality toward the research.

With the research receiving such angst by the public and members of congress, they accepted the commission's proposal of a funding moratorium. Even the split in the President's commission was pretty close (which to me says something) with this ....

"There is no legislation pending in Congress to impose a moratorium on SCNT research. On July 12, 2002 Dr. Maxine Singer, President of the Carnegie Institution, presented the Council on Bioethics with a petition against a moratorium and a ban on SCNT. Over 2,000 medical schools and university science department faculty members signed the petition.. "The petition signals that a large group of informed medical and scientific opinion in this country does not agree with the Council's call for a moratorium," said Dr. Singer. "The petition amounts to an urgent request to allow this promising research to go forward in the interest of millions who are afflicted with severe childhood and adult illnesses." The Council for the Advancement of Medical Research organized the petition. "

They don't want a Senator Brownback trying to completely banning all of their research, so the council accepted the moratorium. It's the misconceptions like Brownback has that threatens the development of the research permanently. They want to take this time to make people more educated on SCNT.

It's great that they have a large group of informed medical and scientific opinions on their petition, but I guarantee I can get an equal number of just-as-informed to argue against it. I'm not even saying that I disagree with SCNT, but I disagree that it's as straightforward in an ethical sense as you're making it out to be.
 

Vadatajs

Diamond Member
Aug 28, 2001
3,475
0
0
Further, your inferrence that unethical behavior is ok, as long as we get useful results in the end (the end justifies the means) is very disturbing.

Strawman.

I'm not advocating sheer pragmatism; read my post again and look for the word "monster." For someone who supposedly spend a year learning about this stuff, you sure are ignorant.
 

Darkhawk28

Diamond Member
Dec 22, 2000
6,759
0
0
Originally posted by: CycloWizard
<blockquote>quote:
<hr><i>Originally posted by: <b>Darkhawk28</b></i>
Cyclowizard,

In order to prevent a congressional ban on stem cell research, they accepted the four year funding moratorium in the hopes that in four years attitudes would be different and public awareness would be greater. The researchers don't feel therapeutic cloning is unethical, just reproductive cloning. The general public and members of Congress, by in-large, don't understand the difference between the two and most people can't get passed the "baby-killing" mentality toward the research.

With the research receiving such angst by the public and members of congress, they accepted the commission's proposal of a funding moratorium. Even the split in the President's commission was pretty close (which to me says something) with this ....

"There is no legislation pending in Congress to impose a moratorium on SCNT research. On July 12, 2002 Dr. Maxine Singer, President of the Carnegie Institution, presented the Council on Bioethics with a petition against a moratorium and a ban on SCNT. Over 2,000 medical schools and university science department faculty members signed the petition.. "The petition signals that a large group of informed medical and scientific opinion in this country does not agree with the Council's call for a moratorium," said Dr. Singer. "The petition amounts to an urgent request to allow this promising research to go forward in the interest of millions who are afflicted with severe childhood and adult illnesses." The Council for the Advancement of Medical Research organized the petition. "

They don't want a Senator Brownback trying to completely banning all of their research, so the council accepted the moratorium. It's the misconceptions like Brownback has that threatens the development of the research permanently. They want to take this time to make people more educated on SCNT.<hr></blockquote>

It's great that they have a large group of informed medical and scientific opinions on their petition, but I guarantee I can get an equal number of just-as-informed to argue against it. I'm not even saying that I disagree with SCNT, but I disagree that it's as straightforward in an ethical sense as you're making it out to be.

Maybe, maybe not. I'll agree it's a severe form of cell manipulation that can potentially be dangerous if used improperly (human cloning for instance), but I feel that through public pressure to do the right thing and government intervention and regulation, that this research just offers way too much potential for way too many people to dismiss on any potential misconceptions. It is this improper use that I debated heavily in my own mind for a long while. We must proceed cautiously, but inevitably, we must proceed. It's time for cure-based medicine instead of disease-based medicine.

Edit: Also, please remember that this is only a substitute for the publically known fetal stem cell gathering (as I've said before, I don't like using aborted babies with this). Plus, stem cells can be taken from the placenta and umbilical cords of ladies that have successfully given birth to LIVE babies. The placentas and cords are usually thrown away anyway, so what's the harm? Please be aware that I feel that even in those cases, that they need to have permission from the woman in order to do that. Adult stem cell research should allowed to proceed unimpeded, I feel.

 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
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Originally posted by: Vadatajs
<blockquote>quote:
<hr>Further, your inferrence that unethical behavior is ok, as long as we get useful results in the end (the end justifies the means) is very disturbing.<hr></blockquote>

Strawman.

I'm not advocating sheer pragmatism; read my post again and look for the word "monster." For someone who supposedly spend a year learning about this stuff, you sure are ignorant.

This is exactly what you said, and what I was referring to with the quote you pulled from my post:
When you look back over history, at monsters like Mengele, the Stanford prison experiment, and the Milgram experiment; valuable lessons were learned by means that were unethical by conventional morality (of the three, Mengele's research is probably the most valuable when it comes to testing the limits of human endurance and the like).
You're stating that the results of these admittedly unethical experiments are valuable and attempting to use that to justify further unethical research. Am I misinterpreting this? I hope so.

We must proceed cautiously, but inevitably, we must proceed. It's time for cure-based medicine instead of disease-based medicine.
As I mentioned earlier (maybe in the other thread), there still is no evidence that embryonic (or non-adult, if you would prefer :p) stem cells have any curative function. It is perhaps more dangerous to tell the public up front that this is the Holy Grail of medicine when it is still in its infancy and no theories regarding it have yet been proven. I agree with the rest of your post though.
 

Darkhawk28

Diamond Member
Dec 22, 2000
6,759
0
0
Originally posted by: CycloWizard
<blockquote>quote:
<hr><i>Originally posted by: <b>Vadatajs</b></i>
<blockquote>quote:
<hr>Further, your inferrence that unethical behavior is ok, as long as we get useful results in the end (the end justifies the means) is very disturbing.<hr></blockquote>

Strawman.

I'm not advocating sheer pragmatism; read my post again and look for the word "monster." For someone who supposedly spend a year learning about this stuff, you sure are ignorant.<hr></blockquote>

This is exactly what you said, and what I was referring to with the quote you pulled from my post:
<blockquote>quote:
<hr>When you look back over history, at monsters like Mengele, the Stanford prison experiment, and the Milgram experiment; valuable lessons were learned by means that were unethical by conventional morality (of the three, Mengele's research is probably the most valuable when it comes to testing the limits of human endurance and the like).
<hr></blockquote>
You're stating that the results of these admittedly unethical experiments are valuable and attempting to use that to justify further unethical research. Am I misinterpreting this? I hope so.

<blockquote>quote:
<hr>We must proceed cautiously, but inevitably, we must proceed. It's time for cure-based medicine instead of disease-based medicine. <hr></blockquote>
As I mentioned earlier (maybe in the other thread), there still is no evidence that embryonic (or non-adult, if you would prefer <img src="i/expressions/face-icon-small-tongue.gif" border="0">) stem cells have any curative function. It is perhaps more dangerous to tell the public up front that this is the Holy Grail of medicine when it is still in its infancy and no theories regarding it have yet been proven. I agree with the rest of your post though.

From all indications, the potential of embryonic stem cell research is enormous, but as of yet, it hasn't been able to fully be realized how enormous it could be. Right now, we know more about adult stem cells but have learned that they only have a limited usage. Only one way to find out how much potential SCNT has is to do the research and find out for sure. I'm 100% though that it will have some significant usage but not fully sure about it being the be-all end-all of medicine. That I won't say, that's not realistic. But what if it only allowed us to grow organs that use the same molecular structure as the patient and eliminates donor lists and possible transplant rejection? I feel that would be well, well, well more than enough to justify the cost.

 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
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Originally posted by: Darkhawk28
From all indications, the potential of embryonic stem cell research is enormous, but as of yet, it hasn't been able to fully be realized how enormous it could be. Right now, we know more about adult stem cells but have learned that they only have a limited usage. Only one way to find out how much potential SCNT has is to do the research and find out for sure. I'm 100% though that it will have some significant usage but not fully sure about it being the be-all end-all of medicine. That I won't say, that's not realistic. But what if it only allowed us to grow organs that use the same molecular structure as the patient and eliminates donor lists and possible transplant rejection? I feel that would be well, well, well more than enough to justify the cost.
By cost, do you mean morally or financially? I would argue that no ends can justify a morally (or ethically) reprehensible means.

Adult stem cells are being researched for the exact type of organ generation that you speak of now. By using the recipient's own stem cells, it's a lock to be a perfect match and avoid immune system rejection (this is the research I'm hoping to do for my PhD :p).
 

Darkhawk28

Diamond Member
Dec 22, 2000
6,759
0
0
Originally posted by: CycloWizard
<blockquote>quote:
<hr><i>Originally posted by: <b>Darkhawk28</b></i>
From all indications, the potential of embryonic stem cell research is enormous, but as of yet, it hasn't been able to fully be realized how enormous it could be. Right now, we know more about adult stem cells but have learned that they only have a limited usage. Only one way to find out how much potential SCNT has is to do the research and find out for sure. I'm 100% though that it will have some significant usage but not fully sure about it being the be-all end-all of medicine. That I won't say, that's not realistic. But what if it only allowed us to grow organs that use the same molecular structure as the patient and eliminates donor lists and possible transplant rejection? I feel that would be well, well, well more than enough to justify the cost.

<hr></blockquote>
By cost, do you mean morally or financially? I would argue that no ends can justify a morally (or ethically) reprehensible means.

Adult stem cells are being researched for the exact type of organ generation that you speak of now. By using the recipient's own stem cells, it's a lock to be a perfect match and avoid immune system rejection (this is the research I'm hoping to do for my PhD <img src="i/expressions/face-icon-small-tongue.gif" border="0">).

Sorry, you're right. Switch that example with curing cancer (edit: or fighting heart disease) and I'll elaborate my previous statement as being the financial cost not the moral cost.
 

Slappy00

Golden Member
Jun 17, 2002
1,820
4
81


That I won't say, that's not realistic. But what if it only allowed us to grow organs that use the same molecular structure as the patient and eliminates donor lists and possible transplant rejection? I feel that would be well, well, well more than enough to justify the cost.

That will take many many man hours of research, is anyone really sure that the organ will function properly when grown in vitro as opposed to vivo, or for that matter how will this new organ be sustained when it is growing? Can it be grown in vivo? I think this can be almost immediatly used in skin grafting which would be nice.
See thats why i like working with bacteria, all the fun none of the fuss of multicellular systems, and although gene cloning is sooooooo 20th century, help from the NIH and USDA is always a good thing :)
 
Feb 10, 2000
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Darkhawk28:

:beer: for your clear, concise explanation of SCNT. I had not really had an accurate mental picture of what was involved in it before reading this thread. From my perspective, any "moral" objection to this is silly and counter-productive, and essentially an example of shoehorning the abortion debate into a completely unrelated, scientifically important issue.
 

Czar

Lifer
Oct 9, 1999
28,510
0
0
Originally posted by: Darkhawk28
Wow, just noticed something. We just had a flame-free discussion at ATPN. <img src="i/expressions/face-icon-small-shocked.gif" border="0">

yeah I noticed that as well, best read here in a long time, thanks for everyone who took part in the discussion :D
 

Vadatajs

Diamond Member
Aug 28, 2001
3,475
0
0
Cyclo:

You are misreading it. I say that ethics are based on the culture's underlying norms and mores, which vary significantly from culture to culture; morality is relative. You asserted that ethics debates have nothing to do with the public's misconceptions:
Ethics councils don't base decisions based on the public's misconceptions, but rather on the ethical implications.
And I was pointing out that those ethical implications are mostly a function of public misconceptions. Maybe Mengele was a bad example, but he operated in a culture that didn't necessarily find his "work" (read:torture) unethical. The other 2 examples were believed to be ethical at the time, but later determined to be unethical due to the extreme mental stress placed upon the participants.

I would have quoted you more, but the forums suck now.
 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
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Originally posted by: Slappy00


<blockquote>quote:
<hr>That I won't say, that's not realistic. But what if it only allowed us to grow organs that use the same molecular structure as the patient and eliminates donor lists and possible transplant rejection? I feel that would be well, well, well more than enough to justify the cost. <hr></blockquote>

That will take many many man hours of research, is anyone really sure that the organ will function properly when grown in vitro as opposed to vivo, or for that matter how will this new organ be sustained when it is growing? Can it be grown in vivo? I think this can be almost immediatly used in skin grafting which would be nice.
See thats why i like working with bacteria, all the fun none of the fuss of multicellular systems, and although gene cloning is sooooooo 20th century, help from the NIH and USDA is always a good thing <img src="i/expressions/face-icon-small-smile.gif" border="0">

All research takes many, many man hours, especially government-funded reseach. ;)
Techinques are currently investigating both in vivo and in vitro, with skin graft (look up 'living skin equivalents') material being one of the furthest advanced at this time.
 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
81
Originally posted by: Vadatajs
Cyclo:

You are misreading it. I say that ethics are based on the culture's underlying norms and mores, which vary significantly from culture to culture; morality is relative. You asserted that ethics debates have nothing to do with the public's misconceptions:
<blockquote>quote:
<hr>Ethics councils don't base decisions based on the public's misconceptions, but rather on the ethical implications. <hr></blockquote>
And I was pointing out that those ethical implications are mostly a function of public misconceptions. Maybe Mengele was a bad example, but he operated in a culture that didn't necessarily find his "work" (read:torture) unethical. The other 2 examples were believed to be ethical at the time, but later determined to be unethical due to the extreme mental stress placed upon the participants.

I would have quoted you more, but the forums suck now.

I would argue that the morality of an issue is based on the culture's underlying norms, whereas ethics are more of a logic-based argument for or against it. Of course, this is really semantics, since obviously the council would have to consider both, so I'll agree with you.
 

Darkhawk28

Diamond Member
Dec 22, 2000
6,759
0
0
Originally posted by: dudeguy
so in otherwords it does involve killing embyos that could have become babies.


SCNT creates FAKE embryos, not real human ones. But if you further manipulate these fake embryos they can develop into reproductive cloning. That's the only danger that there is with all of this.

Remember, these are unfertilized eggs (not touch by a male's sperm) that have had its nucleus extracted. Then they inject the egg with cells from the donor, incubate them until they're a blastocyst-like state, then extract the stem cells they've produced.

The only real, real moral issue for me, like I said, is keeping people from further manipulating them into creating a real, human embryo. That would not be good, in my opinion.
 

dudeguy

Banned
Aug 11, 2004
219
0
0
Originally posted by: Darkhawk28
Originally posted by: dudeguy
so in otherwords it does involve killing embyos that could have become babies.


SCNT creates FAKE embryos, not real human ones. But if you further manipulate these fake embryos they can develop into reproductive cloning. That's the only danger that there is with all of this.

Remember, these are unfertilized eggs (not touch by a male's sperm) that have had its nucleus extracted. Then they inject the egg with cells from the donor, incubate them until they're a blastocyst-like state, then extract the stem cells they've produced.

The only real, real moral issue for me, like I said, is keeping people from further manipulating them into creating a real, human embryo. That would not be good, in my opinion.

so in otherwords there is not a point in which if implanted the embryo could become a human, as the unfertilised normal cells have been removed fromt he egg case, and some other ones put in, which obviously arent capable of starting a pregnancy.
 

Darkhawk28

Diamond Member
Dec 22, 2000
6,759
0
0
Originally posted by: dudeguy
Originally posted by: Darkhawk28
Originally posted by: dudeguy
so in otherwords it does involve killing embyos that could have become babies.


SCNT creates FAKE embryos, not real human ones. But if you further manipulate these fake embryos they can develop into reproductive cloning. That's the only danger that there is with all of this.

Remember, these are unfertilized eggs (not touch by a male's sperm) that have had its nucleus extracted. Then they inject the egg with cells from the donor, incubate them until they're a blastocyst-like state, then extract the stem cells they've produced.

The only real, real moral issue for me, like I said, is keeping people from further manipulating them into creating a real, human embryo. That would not be good, in my opinion.

so in otherwords there is not a point in which if implanted the embryo could become a human, as the unfertilised normal cells have been removed fromt he egg case, and some other ones put in, which obviously arent capable of starting a pregnancy.

It would take a deliberate action to create a viable human embryo. To do so, would require much more manipulation of the cells to do that. What I've described prior is what they call THERAPEUTIC CLONING. What you are worried about is REPRODUCTIVE CLONING. That's what I'm against.

Oh btw, to do reproductive cloning, it must be deliberately done. It can't be done by accident. It would be like you bumping into a lady at the grocery store, your penis falling inside of her and you impregnating her.

 

Czar

Lifer
Oct 9, 1999
28,510
0
0
saw this just now
http://news.bbc.co.uk/2/hi/health/3609992.stm

Britons attack US cloning ban bid
Top British scientists are backing an international campaign to stop the United States obtaining a worldwide ban on all types of human cloning.
The Royal Society is among 68 academies urging the UN to ban reproductive but not therapeutic use of the technology.

President George Bush's administration wants a complete ban, which the UN could introduce as early as October.

Member states would not be compelled to sign up but scientists fear such a treaty could stifle stem cell research.


'Will not sign'

Professor Richard Gardner, chairman of the Royal Society's working group on stem cell research and cloning, said: "It is clear that if the UN bans all forms of human cloning, the UK, and other countries which currently permit carefully regulated therapeutic cloning, will not sign up to it."

Scientists who oppose a complete ban believe it could backfire by halting efforts to stop maverick cloning scientists.

Prof Gardner continued: "To effectively stop cowboy cloners claiming that their work on human reproductive cloning is acceptable, because it is not outlawed throughout the world, a UN convention must be passed that all countries are willing to endorse."

He said a clear distinction by the UN between reproductive and therapeutic cloning would "provide invaluable guidance in passing effective legislation".

He added that it should be noted the US had not yet banned reproductive cloning because of its attempts to include therapeutic cloning in the ban.

Last year the UN, which could introduce a ban at its 59th General Session in October, voted by a slim margin to postpone the decision, despite powerful lobbying by the US.

Earlier this month, scientists from the University of Newcastle were granted a licence to clone human embryos for medical research.

Stem cells from early embryos could potentially be used to provide new treatments for incurable diseases such as Alzheimer's, diabetes and Parkinson's.