Is therapeutic cloning obsolete?After years of urging the public and governments to support the destruction of embryos, scientists may have led them up a blind alley.
But one issue will dominate: ten years after Dolly the sheep was cloned, is therapeutic cloning ready to be mothballed? Only a few days ago an article in the leading journal Nature brought amazing news. (1) A Japanese team at Kyoto University has discovered how to reprogram skin cells so that they "dedifferentiate" into the equivalent of an embryonic stem cell. From this they can be morphed, theoretically, into any cell in the body, a property called pluripotency. It could be the Holy Grail of stem cell science: a technique which is both feasible and ethical. "Neither eggs nor embryos are necessary. I've never worked with either," says Shinya Yamanaka. (2) The first instalment of his research appeared a year ago -- and was greeted with polite scepticism by his colleagues. At the time they were mesmerised by dreams of cloning embryos and dissecting them for their stem cells. The previous head of the International Society for Stem Cell Research, Lawrence S. B. Goldstein, had even dismissed reprogramming as quixotic. "If there are scientists who morally oppose [embryonic] stem cell research and want to devote their energies to uncovering alternatives, that’s fine," said Goldstein. "But in no way, shape, or form should we ask the scientific community and patient community to wait to see if these new alternatives will work." (3) Now, however, ten years after Dolly, not one scientist anywhere using a cloned human embryo has created a stem cell line. Not one. And a Japanese Don Quixote has. This is mainstream research, not an eccentric theory from wild-eyed pro-lifers. Yamanaka's work has been confirmed by two other teams affiliated with the Massachusetts Institute of Technology, Harvard University and the University of California, Los Angeles -- both of them headed by ardent supporters of embryonic stem cell research.
They say that the reprogrammed cells meet all the tests of pluripotent cells -- they form colonies, propagate continuously and form cancerous growths called teratomas, as well as producing chimaeras. "Its unbelievable, just amazing," says Hans Schöler, a German stem cell expert. "For me, it's like Dolly. It's that type of an accomplishment." (4) What Yamanaka did was to take a mouse skin cell and introduce into it four proteins which trigger the expression of other genes to make it pluripotent. "It's easy. There's no trick, no magic," he says. Naturally, it's easy only for experts at the moment. There are some worrying issues to contend with: one of the proteins seems to contribute to cancers in 20% of the mice. But since cancers are the Number One problem with embryonic stem cells as well, it is not surprising that stem cells induced to an embryonic-like state share this embryonic flaw.
Harvard researcher Chad Cowan says that it will change the field: "The most amazing thing about these papers is you now take this whole idea of reprogramming out of the hands of cloning specialists and put it into the hands of anyone who can do molecular and cell biology." (5) Now the race is on to apply the technique to human cells. "We are working very hard -- day and night," says Yamanaka. Will this disruptive technology open up ethical avenues in the promising field of stem cell research which do not involve turning women into battery hens for their eggs and destroying embryos? At the moment, the stem cell grandees, like all establishment figures, have no plans to change their tune. One of the stars of Cairns, MIT's Rudolph Jaenisch, told Nature that therapeutic cloning remains "absolutely necessary". And executives from embryonic stem cell companies were not optimistic about the new technique either. Because it involves tinkering with the genome, it could be dangerous, warned Thomas B. Okarma, of Geron, the leading private company in the field. Getting approval from regulatory authorities would therefore become far more complicated. (6) What else could he say? No doubt manufacturers of video tapes muttered about serious flaws in DVDs when they first appeared on the market.
With an ethical solution looking quite plausible, the pressure will be on scientists to justify embryonic stem cell research. Two years ago, Dr Janet D. Rowley, an Australian working in the US who is an implacable foe of the Bush Administration's policy, dismissed ethical solutions. "We have extremely limited research dollars, and to use them to study these alternatives is wrong," she declared. "That money should be available for actual research." (7) But now stem cells derived from embryos are starting to look like dead-end "alternatives".
Don't expect supporters of embryonic stem cell research to respond rationally, not in the short term, at least. The other day, Democratic Caucus Chairman Rahm Emanuel told the US House of Representatives as he voted to overturn the Bush policy: "It is ironic that every time we vote on this legislation, all of a sudden there is a major scientific discovery that basically says, 'You don't have to do [embryonic] stem cell research.' " (8) Connect the dots, Mr Emanuel. Maybe you don't have to.
Michael Cook is editor of MercatorNet. Notes
(1) "Simple switch turns cells embryonic". NewsNature. 7 June 2007. (2) "Simple switch turns cells embryonic". NewsNature. 7 June 2007.
(3) "Scenarios for stem cell creation debated". JAMA. 22/29 June 2005. (4) "Simple switch turns cells embryonic". NewsNature. 7 June 2007.
(5) "Teams Reprogram Differentiated Cells -- Without Eggs." Science. 8 June 2007.
(6) "A Long, Uncertain Path for New Cell Technique." New York Times, 7 June 2007. (7) "Scenarios for stem cell creation debated". JAMA. 22/29 June 2005.
(8) "Darn Cells. Dividing Yet Again!" Washington Post. 10 June 2007
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Next week the international grandees of therapeutic cloning gather in Cairns, Australia, the sun-soaked gateway to the Great Barrier Reef, for their annual conference. They have serious strategic issues to deal with along with their scientific papers and posters: persuading governments to open their wallets, ensuring that the Bush Administrations restrictions on their work are lifted, allaying the public's qualms about creating embryos solely for research.
Comments (10)
Yedge said...Why are Scientists so hell bent on proceeding with such dubious research?
This article pushes all the right buttons...or should I say cells :-)
Yedge
-- | Saturday, 16 June 2007 at 5:26 pm
Dan said...Scientific progress is more often than not accidental and haphazard. Having lay politicians guide its direction seems more than a little peculiar.
Therapeutic cloning and its alternatives may well end up offering different solutions for different human problems. With the presumed assent of the parliament, NSW and Australia will be able to be at the forefront of research of what may well prove to be a boon to humanity.
Australia | Sunday, 17 June 2007 at 1:34 am
Mary A. Hamilton said...SCNT may never work in primates for biological issues unique to them (for example, in successfully ‘cloned’ mammals the centrosome is maternally derived; it’s paternally derived in primates.) Putting women’s health/lives at risk to supply materials for this research at todays level of knowledge and technology is unacceptable.
Attempts using non-primate eggs have been made since 1996 by the world leader in SCNT, Advanced Cell Technology (Mass. USA). Even if successful, these cells are primarily for research, not therapeutic, value.
SCNT in primates is moot. Feasibility of this option is more important than a metaphysical debate.
United Kingdom | Sunday, 17 June 2007 at 10:37 pm
Minerva Schwartz said...The only therapy ‘therapeutic cloning’ has been shown to have success is the one generally banned when discussing its use in humans - reproduction.
No animal studies exist where the organism was successfully treated from cells harvested from a ‘clone’ at the embryonic stage. Instead, these animals had to be grown to at least the stage equivalant to a 5 month old fetus before implanted harvested ‘clone’ cells did not cause severe complications in the host animal.
So, why is practical application omitted?
United Kingdom | Sunday, 17 June 2007 at 10:50 pm
Silvername said...Embryonic stem cell research is immoral, evil, wrong, it must never be allowed or tolerated.
And it doesn’t work, there is not even a single cure that has come from ESCR.
On the otherhand, adult stem cell research is moral and it is effective, there are already 70 diseases which can be cured thanks to ASCR.
The fact that these secular fanatics and rabid Bible-haters keep on pushing ESCR despite the clear advantages of ASCR only reveals their true immoral “mad scientist” agenda and mentality.
BAN EMBRYONIC STEM CELL RESEARCH!!!
Philippines | Monday, 18 June 2007 at 2:55 pm
Fr. Walter Macken said...If the great Japanese scientist can prove that stem cell research is unnecessary that will be a great boon to research. It is a grave error to presume that immoral research (destroying embryos, living human beings in potency) can lead to improving humanity. No man, no woman is a mere material fact,a mere body, a mere “corpse”. Every human person has these deep inner residues, that core of the character that leads one forwards, or backwards. It is not ONLY a matter of what happens after death to a person who has flouted morality in this life. It is that life is inadequate, unfulfilled, incomplete, when morality is cast aside.
This is a philosophical and human consideration. It has nothing to do, of itself, with the Bible. If you accept the Bible, morality is made easier. But surely it is possible for a thinking person to realise that the purpose of life is the spiritual improvement of each single person, and that imposing death on the unborn is going to leave each person who participates in that all the poorer, bereft of their humanity, incompleted. We cannot be supporters of death. There is too much death in this world. We have to be supporters of life. There are other ways of fighting disease than chopping up unborn babies.
Walter Macken, Galway, Ireland.
Ireland | Tuesday, 19 June 2007 at 2:48 am
Joseph said...We have to make sure that in the future we don’t clone these scientists.
Australia | Friday, 22 June 2007 at 3:25 pm
Malcolm Lyons said...The deceiving bunch of people involved in the very profitable human embryo industry are doing much harm and a great disservice to society. The thousands of millions of dollars they have received should have gone to the very promising adult stem cell research groups.
Supporters of this inhuman treatment of human embryos have succeeded in playing the emotional game. “It is good for you” they say - and it works. They use this tactic whenever there is a desire to change prevailing moral values. People who oppose these changes have basically one line to offer, namely that it is wrong.
Many politicians are guilty of succumbing to the emotional blackmail. Many of us are equally guilty for voting in these politicians.
Australia | Friday, 22 June 2007 at 11:27 pm
Anthony Khoudair said...The following definition from the “cite-sciences” web site was quite enlightening: “Stem cells are classified into several types : 1) totipotential: these are the first cells of the embryo (up to 8 cells). They have the capacity to produce all the cells, tissues and organs that make up the human body; 2) pluripotential: these are embryonic cells from the first 16-32 cells. They produce about two hundred different cell types, but no one of them can produce an entire human being...”
Two pieces of information from your backgrounder by Dianne Irving are also important:
1) the phase of totipotency for the embryonic cells seems to be the first 2-3 days of gestation [according to O’Rahilly and Muller, Human Embryology and Teratology (3rd ed., New York: Wiley-Liss, 2001)];
2) The commonly accepted definition of “embryo” takes in the first eight weeks of gestation, way beyond the first few days of totipotency of the embryonic cells.
The work of the Japanese scientist Yamanaka must obviously be encouraged, but with one cautionary ethical note: the scientific drive towards the obtaining of pluripotent cells must not enter the ethically dangerous zone of the boundary between pluripotency and totipotency, for once we reach totipotency, we would seem to be dealing with an embryonic state “which can produce an entire human being”, i.e., a human being, or clone. To keep up the push towards pluripotency, it would seem prudent to try to indicate just what the ethically safe “playing field” is.
Australia | Wednesday, 4 July 2007 at 11:04 am
Kory said...Those stupid scientists need to stop cloning animals and such. its just not right.
United States | Monday, 21 January 2008 at 2:06 pm
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