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Scientists use 'virgin birth' technique(Cloning Alert!!)
BBC News ^ | 11-26-2001 | Dr David Whitehouse

Posted on 04/25/2003 5:37:42 PM PDT by cpforlife.org

By BBC News Online science editor Dr David Whitehouse

In many ways the most interesting announcement from Advanced Cell Technology was not that its scientists had produced a human embryo clone - significant though this was (if confirmed) - but that the researchers had also got a human egg cell to start dividing on its own just like an embryo.

It sounds something like the virgin birth. Technically, it is called parthenogenesis.

The human egg cell develops into an embryo without the addition of any genetic material from a sperm cell. The embryo would be a clone of the mother.

It, too, could be a source of useful stem cells to grow into replacement tissues and organs to treat degenerative diseases.

And for some researchers, it overcomes the ethical dilemmas of "conventional" cloning because a mammal parthenote is incapable - so far as current science thinking is concerned - of become a viable foetus; for others, it will be just another example of science going too far.

No father

Parthenogenesis has been observed in many lower animals, especially insects such as aphids. In many social insects, like the honeybee and the ant, parthenogenesis gives rise to male drones. Fertilised eggs produce female workers and queens.

Some larger animals can reproduce this way - there are a few lizards, for example. Parthenogenesis has also been artificially induced in frogs and snakes, although it quite often results in abnormal development.

Persuading unfertilised eggs to start dividing like embryos was achieved in mice and monkeys fairly recently, but it has never been artificially induced in humans - until now, it would seem.

Normally, it is only when a sperm cell merges with an ovum and a full set of genes is assembled that an embryo is formed and starts to develop.

Mature eggs and sperm usually have only half the genetic material of a typical body cell, to prevent an embryo from having a double set of genes following conception. Eggs halve their genetic complement relatively late in their maturation cycle.

Diseased heart

But if an egg cell is somehow activated before that stage, it still has a full set of genes - and could develop into a functioning embryo clone.

Stem cells derived from a parthenogenetically activated embryo would be unlikely to be rejected after transplantation. Such cells might also raise fewer moral dilemmas for some people than would stem cells derived through the "conventional" cloning process.

The ACT scientists suggest that one way this technique could be used would be for a woman with heart disease to have her own egg cells collected and activated in the laboratory to produce stem cells. The stem cells could then be coaxed to become cardiac muscle cells that could be implanted back into the woman to patch a diseased area of the heart.

Using a similar technique to create stem cells to treat a man would be trickier. It would involve some genetic manipulation, such as transferring two nuclei from the man's sperm into an egg that had been stripped of its nucleus. Such "male-only conception", however, is highly speculative and few believe it will ever be possible.

Expected cloning

Researchers have reported prompting eggs from mice and rabbits to divide into embryos by exposing them to chemicals. As early as 1983, it was demonstrated that stem cells isolated from parthenogenetic mouse embryos could form a variety of tissues, including nerve and muscle.

In ACT's parthenogenesis experiments, 22 eggs were exposed to chemical activation. After five days of growing in culture dishes, six eggs had developed into what appeared to be embryos, but none clearly contained the so-called inner-cell mass that yields stem cells.

Because for females parthenogenesis would involve cell manipulation with no additional genetic material, it may prove to be a more ethically acceptable method of producing stem cells than the conventional transfer of nuclear DNA material from another person.

Sunday's announcement is a major advance in human genetic manipulation and is more surprising than the production of the first human embryo clones, which commentators had been expecting for some time. It is also an advance with potentially even more far-reaching implications.


TOPICS: Business/Economy; Constitution/Conservatism; Crime/Corruption; Culture/Society; Philosophy
KEYWORDS: bioethics; cloning; parthenogenesis
Credit goes to Freeper MHGinTN for finding this article and pointing it out. Great find M!
1 posted on 04/25/2003 5:37:42 PM PDT by cpforlife.org
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To: MHGinTN; hocndoc; Coleus; Remedy; RLK; Canticle_of_Deborah; Mr. Silverback; ...

Please let me know if you want on or off my Pro-Life Ping List.

2 posted on 04/25/2003 5:41:06 PM PDT by cpforlife.org (“My people are destroyed from lack of knowledge.” Hosea 4:6)
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To: cpforlife.org
I'm holding out for asexual budding, do away with all this
sexual nonsense.
3 posted on 04/25/2003 5:43:49 PM PDT by tet68 (Jeremiah 51:24 ..."..Before your eyes I will repay Babylon for all the wrong they have done in Zion")
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To: MHGinTN
MHGinTN,

The floor is yours, sir.
4 posted on 04/25/2003 5:48:02 PM PDT by cpforlife.org (“My people are destroyed from lack of knowledge.” Hosea 4:6)
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To: cpforlife.org
I recall reading about parthengenesis to produce albino turkeys some 35-or-so years ago. Nuttin' new under the sun, it seems...
5 posted on 04/25/2003 6:16:23 PM PDT by The Duke
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To: cpforlife.org
the researchers had also got a human egg cell to start dividing on its own just like an embryo.

Not quite. It didn't start dividing on its own. It started dividing when it was activated.

From the same article:

In ACT's parthenogenesis experiments, 22 eggs were exposed to chemical activation.


If eggs started dividing into embryos on their own, quite a few women would be very surprised.

A well-known science writer purposely muddied the waters about this when he wrote an op-ed article for the NYTimes some years back.

  1. First he said that experimentation in parthenogenesis showed that an egg could start dividing and become an embryo.
  2. Then he argued that, if pro-lifers say embryos are human beings, then they have to say human eggs are human beings (since the eggs can be changed into embryos).
  3. He "reasoned" that a loss of an egg during menstruation would have to considered abortion by the pro-lifers.
  4. In his rush to poke fun at the image of pro-lifers defending eggs from menstruation, he neglected to remember he himself had mentioned the necessary "activation" of the egg earlier in his own article.

An egg and an embryo are NOT the same thing.

6 posted on 04/25/2003 6:31:33 PM PDT by syriacus (Schumer is a Smellfungus. Schumer is a Shmellfungus. Schumer is a Schmellfungus.)
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To: J. Neil Schulman; general_re; RS; hocndoc
Ping-a-ling
7 posted on 04/25/2003 6:44:23 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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But if an egg cell is somehow activated before that stage, it still has a full set of genes - and could develop into a functioning embryo clone. I challenge general_re and RJ Cogburn to find an article or piece of research that makes use of 'parthenogenesis' to stimulate a haploid ovum into forming a useful embryo, or any tissue that would be utilitarian in treating any human disease. If there is one, I have yet to find it, so I'd like to read it. I've speculated (due to the invitation at addressing the possibilities) that if a haploid could be stimulated to grow soemthing akin to useful tissues for research purposes only, that would be problematic, to me--since I count it improper tampering-- but it wouldn't be experimentation on an individual alive embryo. Would anyone like to take this further, offer articles or peer reviewed papers on parthenogenesis using haploid ova?
8 posted on 04/25/2003 6:51:53 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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To: MHGinTN
I challenge general_re and RJ Cogburn to find an article or piece of research that makes use of 'parthenogenesis' to stimulate a haploid ovum into forming a useful embryo, or any tissue that would be utilitarian in treating any human disease.

I should have guessed ;)

Okay, fair enough - I accept, but I'll need at least a few days to really do a proper search.

9 posted on 04/25/2003 7:38:12 PM PDT by general_re
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To: general_re
No animus intended; we'll both likely learn from the experience. BTW, I'll look also, 'cause I need to know as badly as you may want to know.
10 posted on 04/25/2003 8:02:31 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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To: MHGinTN
Well said. Let me ask you a question about diploid parthenogenesis, though - is your opposition to it absolute, or would you moderate your position if diploid parthenotes turned out to be universally non-viable?
11 posted on 04/25/2003 8:06:48 PM PDT by general_re
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To: general_re
First, the tissue that 'might' be derived from such exploitation would be severely compromised for any application in medical terms, at least from the perspectives I've studied ... the half-complement of chromosomes would be like timebombs, possibly even tumor causing if implanted or injected into a patient for some disease state treatment. Second, if somehow the haploid began to differentiate in a staggered or mutagenic fashion, what would be in evidence is a purposely conceived severely handicapped human lifeform ... not a thing I could endorse, even though it would have zero viability for full gestational development.

Between you and me and the dog named blue, what I'm very worried about are the cross species cloning efforts being done in Japan and South America. It will not be long 'til someone tries a human-swine, or bovine-human. If cordblood stem cells could be coaxed into tissue differentiation yielding useful tissues or organs, I'm not at all opposed to implanting such in a swine or other animal (great ape perhaps) to support it until growth to usable development was evidenced. I am wary of the scientists jumping directly to human models, without the exhaustive other mammalian models being explored first. It has to be motivated by things like greed and lust for acclaim. Hurrying such delicate procedures is disasterous and usually sacrifices lives, human lives. [Experience with the pharmaceutical industry showed me that years ago.] I will have to think more on a reply if and when we find more on the possibilities.

12 posted on 04/25/2003 8:42:35 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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To: cpforlife.org
read later
13 posted on 04/26/2003 12:14:28 AM PDT by LiteKeeper
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To: 2nd amendment mama; A2J; aposiopetic; attagirl; axel f; Balto_Boy; bulldogs; Charlie OK; cgk; ...
ProLife Ping!

If anyone wants on or off my ProLife Ping List, please notify me here or by freepmail.

14 posted on 04/26/2003 6:15:18 AM PDT by Mr. Silverback (God Bless Michael Speicher and those who wait for him.)
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To: MHGinTN
I think the discussion on this thread is on a little different topic, but I wondered if you saw this small segue provided by Scientific American: Monkey Cloning Failures Cast Doubt on Feasibility of Human Reproductive Cloning(FR thread)

As you already know, primate reproductive cloning is encountering problems at this time.

15 posted on 04/26/2003 6:38:39 AM PDT by syriacus (Schumer is a Smellfungus. Schumer is a Shmellfungus. Schumer is a Schmellfungus.)
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To: syriacus
Something which is key is understanding the vast difference in stimulating a typical organ cell to replicate itself and perhaps an organ, and the quantum level higher event of stimulating a sex cell to begin dividing and differentiating into organs and organ tissues.

The capability of a sex cell with 46 chromosomes (ovum that hasn't matured fully, to reduce its chromosome complement to 23) to be stimulated into dividing is more than just that cell reproducing itself, it is that cell reproducing the individual human from whom the cell was removed!

At the moment when cell division in a conceptus begins, the conceived individual human loses, with each cell division and subsequent division, some capability to build the broadest number of tissue and organ categories. That is an important distinction to note, as the difference between average somatic cells and sex cells. It is the reason why theoretically, two sperm could be fused (each has 23 chromosomes) to form a conceptus and thus an alive embryo. It is also the reason the technician could not use two kidney cells or two liver cells or two glial cells, or even coax one of those cells to begin the differentiation journey that builds the organs and organ systems of an individual human life.

16 posted on 04/28/2003 11:42:06 AM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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.
17 posted on 04/28/2003 12:22:40 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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18 posted on 04/28/2003 2:13:10 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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To: MHGinTN
Thanks for the explanation, MHGinTN.
19 posted on 04/28/2003 2:36:45 PM PDT by syriacus (Our tagline composers are assisting other customers. Your input is important to us. Enjoy the music)
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20 posted on 04/28/2003 6:31:11 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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21 posted on 04/29/2003 2:27:46 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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To: cpforlife.org
"Credit goes to Freeper MHGinTN for finding this article and pointing it out."

Well, actually, I posted this topic on 4/24, since I try to post articles on this general topic from various approaches, though I guess you realize I favor stem cell research of all sorts.

"Discovery could silence debate over stem cells"
http://www.freerepublic.com/focus/f-news/899470/posts
22 posted on 04/29/2003 3:31:14 PM PDT by RJCogburn (Yes, I will call it bold talk for a......)
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To: RJCogburn
Relax, RJ, the article of this thread is from the BBC media system ... different from your posted article. You did, however, post the first article on parthenogenesis, as best I can discover.
23 posted on 04/29/2003 4:14:07 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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To: general_re
virgin birth, eh?

Perhaps THIS is how Anakin Skywalker was conceived?
24 posted on 04/29/2003 5:26:10 PM PDT by Skywalk
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To: Skywalk
Speaking of Anakin Skywalker, I've got a major project I'd like to offer to G.Lucas, for his development into two or three movies. You wouldn't know how to get a submission request to him, would you?
25 posted on 04/30/2003 6:14:32 AM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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To: MHGinTN
LOL

Unfortunately no. You could try going through some fan sites like theforce.net, and seeing if you can work your way up. Other than that, I'd have no idea.
26 posted on 04/30/2003 1:20:23 PM PDT by Skywalk
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