posted
I was reading this article, which talks about a method that has been divised that causes unfertilized eggs to divide up until the point at which they reach the blastocyst stage. In theory they'll be able to harvest stem cells from them, and the idea is that getting the stem cells this way will satisfy the people who are opposed to harvesting them from left over IVF blastocysts, since the parthogenic blastocysts wouldn't be capable of developing into a viable fetus anyway. So, those of you who are opposed to embryonic stem cell research, what do you think of this? Would this, in your eyes, be an acceptable source of embryonic stem cells (assuming, of course, that they're able to extract usable stem cells from the blastocysts in question)?
Posts: 16059 | Registered: Aug 2000
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posted
I think it would be fabulous! I am not vehemenantly opposed to embryonic stem cell research, but I do have deep concerns. Till now, the solution I've been most comfortable with is using stem cells harvested from umbilical cords. This new solution also would allow researchers to continue stem cell research without becoming ensnared in the moral/ethical issues of using stem cells harvested from (possibly) viable embryos.
posted
That sounds wonderful. I don't have a lot of ethical issues with the normal kind of embryonic research as long as they were from embryos that were left over and not created for that purpose, but this is much, much better. Posts: 26077 | Registered: Mar 2000
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posted
I just read the article. My initial response is that I agree with kat--I've never had that much of a problem with medical use of embryonic stem cells that are not created for the purpose of experimentation and will be destroyed anyway (e.g. from fertility treatments.) This new technique sounds promising, though I must admit it kinda squicks me out how scientists can trick an egg into thinking it is fertilized. It doesn't seem to be a very long step until we get to the whole "who needs men, anyway, if we don't need their sperm" argument, which, as a male, I have several objections to. Posts: 786 | Registered: Jun 2003
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posted
The thing is, so far everyone who has responded has been at least somewhat okay with the idea of harvesting stem cells from embryos left over from IVF procedures. I'd be surprised if people with that position *didn't* think this was a good thing. I'm just curious whether it would satisfy those who are strongly opposed to conventionally aquired embryonic stem cells.
Posts: 16059 | Registered: Aug 2000
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posted
Assuming the egg can not be a person even though it has two sets of chromosones, I would not object. With proper precautions in place. Just what we need, women in countries that aren't good at thinking of them as people anyway forcibly harvesting their ova. :shudder:
However, if the two sets of chromosones can make a whole person, I would object. I don't care how you get the person, they still deserve to live, not be harvested for parts.
Posts: 2283 | Registered: Dec 2003
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posted
I have serious problems with harvesting stem cells from ebryos. I wouldn't have problems with this potential method.
I am fairly confident that we will find a feasable alternative source for stem cells. This is one possibility. There are many others. I am pleased that there is no federal funding going toward stem cell research that will be harvesting embryos, but I also see the enormous potential that stem cell research holds.
Posts: 16551 | Registered: Feb 2003
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quote: I am pleased that there is no federal funding going toward stem cell research
I agree. Though, unlike Porter, I have few moral qualms with limited embryonic stem cell research--basically, only on leftover IVF embryos--I am glad that it is not federally funded. I am also very glad that it is not prohibited, either. When it comes to ethical issues where many good people are divided, I think in general that the federal government should butt out. Let the funding come from either private donations (like the Christopher Reeve foundation) or from the state level (like the recent California proposition thingy.)
Posts: 786 | Registered: Jun 2003
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posted
I am utterly 100% against embryonic stem cell research, so I'm your target questionee.
As to this procedure, at first blush I'd say I don't have a problem with unfertilized eggs being used to produce stem cells (assuming voluntary donations of eggs, etc.). I haven't thought through all the implications yet, but the turning point for me has always been fertilization. Before that, I have moral qualms but not enough to make it illegal.
quote:Let the funding come from either private donations (like the Christopher Reeve foundation) or from the state level (like the recent California proposition thingy.)
California's investment in future-tech. I don't know if it is really the state's job to invest in R&D, but this will likely make California a leader in that field.
Now if we could just solve our housing crisis.... Posts: 2506 | Registered: Jul 2003
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posted
Where's the difference between this and cloning? We're taking the mother's complete gene sequence and preventing the egg for ousting half its DNA as it would normally do when fertilized by sperm. But it's dividing as if it were fertilized, and it's still diploid. Sure it doesn't have paternal DNA, but it still has a complete set of chromosomes. How are we sure that this won't become a human? Where's the difference between this and cloning?
If we were to clone this woman we'd take an egg, remove the nucleous and insert the nucleous from another one of her cells that is diploid. Then we'd induce it to divide. Sounds awefully similar to me. If this is Ok shouldn't any clone be acceptable as well?
Posts: 3243 | Registered: Apr 2002
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posted
Yeah. It just seems a little inconsistent to be pro this but against human cloning both in general and as a source of stem cells.
Heck, this might be more viable than a regular human clone. Primate eggs have cell division signallers that are lost when the original nucleus is removed, something that scientists haven't been able to completely work around yet. In this case that isn't a problem. Of course, you wouldn't be able to check unless you tried to take it to term, and imagine the kerfuffle that'd ensue if it *was* viable and someone gave birth to a human clone?
And so you have to take it on a leap of faith that this isn't a human life and draw a potentially arbitrary line in the sand much like those who say a blastocyte isn't human. It seems to me, barring more data, that the only way to be consistent if you're against the creation of embryos for stem cell harvesting that contain paternal DNA you should be against this as well.
Unless there's something I'm missing. The article gives precious little information. Maybe I'll scope the referenced journal. Go go gadget university library!
Edit: Scratch that, the artical is from the December issue of Reproduction. They haven't indexed it on their site yet and I don't see any hard copies in our library.
Second edit: That should have been primates, not mammals. Clearly we've been cloning mammals for a while (hello, Dolly!)
[ December 02, 2004, 01:53 PM: Message edited by: Bob the Lawyer ]
Posts: 3243 | Registered: Apr 2002
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posted
BtL, that is a good point. Sounds very much like cloning. So if cloning bothers a person, this will likely bother them.
I am not all that bothered by the idea of cloning. I dunno, I guess I have never heard of a convincing enough reason to be bothered. What are identical twins but clones? Now we can have identical groups of people that have an age difference and happen on purpose. As long as a clone is considered fully human with all the rights any other human has, I don't see a problem. Just a change in paradigm and a new thing to accept and deal with.
Now, if we had the power to play with consciousness and change what is in someone's brain, as we see in many Sci-fi stuff, then I might be more disturbed.
Incidentally, feel free in this thread to try and convince me that cloning is a bad thing. Posts: 7050 | Registered: Feb 2004
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posted
The article says the cell can't become a person. Assuming that's true, I don't mind taking the stem cells because they didn't kill anyone to do it. Again, this has potential for abuse of women in other countries, but i'm not sure how to stop that even if the US doesn't pursue this technology.
If Bob is right and this is cloning, then I'm dead set against it. A cloned person is still a person and deserves to live.
As for knowing for sure, I suppose we'd have to take a bunch of cells to term. I assume it would be done with mice or monkeys or something. If the egg can't proceed past a certain stage becuase the two sets of chromosones won't talk to each other, then we'd know. If they grow into little baby mice, we'd still know. Since this never came up in high school biology, I have no idea if the second set of mom's chromosones could just fill in for the missing set from dad. But I agree with Brian, parthogenic reproduction is a bit scary.
Posts: 2283 | Registered: Dec 2003
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posted
For me the difference is that these cells cannot develop into a human. If you add another set of the mother's chromosomes so that it has full parental DNA, then it can become a full person, and it's a whole different ball game for me.
Even if this were done, this wouldn't be a clone, because the child's DNA would not be identical to the mother's. All of the children's DNA would come from the mother, but it wouldn't have all the same sets.
Or am I wrong about this not being a clone?
Posts: 16551 | Registered: Feb 2003
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posted
That's why I want to see the actual journal, Porter.
quote:“Embryos” created by the procedure do not contain any paternal chromosomes – just two sets of chromosomes from the mother – and so cannot develop into babies.
quote:Human eggs contain two sets of chromosomes, one of which is normally jettisoned within two hours of fertilisation. Swann and his team used a standard chemical treatment to prevent this, so both sets in the parthenogenetic embryos come from the mother.
So they seem to be implying that the cell has 2 sets. I'm not a molecular biologist and I've never taken a course in embryology so I don't know any more than the article tells me. I don't understand why having both sets from the mother would make a difference if you consider both that clones are possible and offspring from the fusion of two eggs or two sperm (so you have either exclusively maternal or paternal DNA) have been performed for years in mice.
If both sets are from the mother that means there was no independent assortment during meiosis (which is contrary to what I learned in my intro Bio courses, but it wouldn't be the first time something was simplified so it could be taught faster) which means the egg is carrying exactly the same code as the mother. You cannot get any closer to a clone than that.
I'm so not an expert on this though. I know just enough about this stuff to hang myself.
Posts: 3243 | Registered: Apr 2002
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quote:imagine the kerfuffle that'd ensue if it *was* viable and someone gave birth to a human clone?
I'm not enough of a scientist to grasp all the nuances that quickly, which is why I qualified my opinion in my first post.
Would this be a clone, though? I don't remember enough about meosis, but doesn't some genetic material get swapped between chromosomes? Which means this cell might have two copies of the same gene where before there were two different ones.
Hopefully someone can extract what I'm really asking from the many errors I'm sure are there.
posted
I know we pass on recessive genes. Anyone know if that's because it's the only gene in the cell or because the dominant strand got booted when the second set of chromosones was ejected?
If the cell only contains some of the chromosones we carry, then it wouldn't be a clone because it would have a different mix of genes. But if the sex cells have all the chromosones and eject half in favor of the other parent's, it would be a clone with the exact same chromosones.
Posts: 2283 | Registered: Dec 2003
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posted
I haven't read the article, but the question is interesting. Like Dag, I'm 100% against embryonic stem cell research except on existing lines.
If there is any possibility that given ideal circumstances, one of these mother-only blastocysts could grow and develop into a person, then I'm against it. If the mother-only blastocysts could not under any (possible or currently technically impossible but theoretically possible) circumstances ever become a person, I have no problem with it at all.
Posts: 5948 | Registered: Jun 2001
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posted
I'm not a molecular biologist, but I do teach HS students about meiosis every year. I'm fairly certain that the first half of meiosis forms cells that have two IDENTICAL sets of chromosomes -- so only half of the mother's genetic information. (Yeah look at meiosis versus mitosis. Going through the animations frame-by-frame is especially helpful.)
No idea what that would mean in terms of likely fatal recessives, or other problems. But it certainly would make it not a clone of the mother.
Posts: 32919 | Registered: Mar 2003
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posted
I'm opposed to funding research with taxpayer dollars.
Why do politicians persist in spending taxpayer dollars on morally divisive practices such as publicly-funded abortions and publicly-funded illegal narcotic trade and publicly-funded highways through wetlands and publicly-funded terrorist backing?
If governments would stick to the job of defending the populace from foreign attack, regulating trade, and securing the rights of the people, we wouldn't be having this discussion.
Politicians have found that fueling enmity and feeding on enmity is more fun and more lucrative than just doing their jobs.
quote: Politicians have found that fueling enmity and feeding on enmity in more fun and more lucrative than just doing their jobs.
I was wondering...could I maybe get a biased opinion, now that the unbiased one has been voiced?
I don't like the war, or Bush....but how exactally, since you obviously have this all worked out, would one defend their country when attacked other than by force or invasion?
Do you eat? Where do you get your food? A supermarket?
How would trade exist in the US without highways? It wasn't that long ago when supermarkets were a new thing....and without a highway infrastructure how many people would die because of lack of timley EMY responce times, getting to and from the hospitals.
quote: Human eggs contain two sets of chromosomes, one of which is normally jettisoned within two hours of fertilisation. Swann and his team used a standard chemical treatment to prevent this, so both sets in the parthenogenetic embryos come from the mother.
I took General Biology 2 last semester, and if I remeber correctly, the union of the gametes activates embryological development. So if both sets come from one parent, there is no union of male and female gametes, and thus development is not commenced.
But don't quote me on that.
Posts: 2756 | Registered: Jul 2002
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Since when did the government owe us a supermarket full of groceries and conveyance to a hospital? Man has done just fine for centuries growing his own food and doctoring himself. Our personal choices to pursue careers other than farming and medicine should not necessitate the creation of new branches of government.
Maybe you think the government owes us fire and police protection too. It used to be that folks put out their own fires and shot evildoers on sight. Our personal choice to build our house so close to our neighbor's house that we put him in jeopardy in the event that our own house should catch fire should not necessitate the government's purchase of a new fire engine. When was the last time a Texas rancher or midwest farmer needed police protection?
Now we've got people who think the government owes them a high speed fiberoptic Internet connection because of their personal choice to turn the stinkin' computer on.
And back to the stem cell thing, our personal choices to keep ourselves and our children alive at all cost should not necessitate the government's funding of research into new methods of prolonging our years spent in front of the TV set.
Posts: 2655 | Registered: Feb 2004
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posted
A neat link in the cloning thread lead me to these quotes.
quote: In parthenogenesis, the egg becomes the sole source of genetic material for the creation of an embryo. It is a mode of reproduction in some species, though not in mammals. In mammals parthenogenesis can begin if an egg is accidentally or experimentally activated as if it had been fertilised - but this parthenote never grows past a few days.
This is because of there a biological phenomenon known as imprinting. During sperm and egg formation in mammals, certain genes necessary for embryo development are shut down with a series of chemical marks, or imprints, some in the sperm, other in the egg. Only when sperm and egg meet are all of the key genes available, allowing proper development.
"...clearly IGF-2 is the key gene," he says. "They managed to get around it but to really get to a situation where the procedure would work as well as [fertilisation with] sperm, you would need to mutate a lot more genes."
Kaguya and one sister were the only live animals resulting from 457 reconstructed eggs.
Since they have experiments showing the egg can not become a people, I can say with reasonable surity that I'm ok with stem cell retrieval from this. Now for a UN resolution protecting women from having their ova harvested against their will or for money. More importantly, to get it enforced.
Posts: 2283 | Registered: Dec 2003
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posted
I really, really would like to see us making a concerted effort toward research involving cord blood, and adult stem cells.
From what I've heard, great advances have been made using these two sources of stem cells, and there is no question of embryonic life involved.
Stuff like this:
quote:TORONTO, April 25 – Injections of adult stem cells into damaged heart tissue significantly improved heart function in patients with severe congestive heart failure, according to results of the first prospective randomized trial of the experimental therapy presented today at the American Association for Thoracic Surgery.
There's also the promising and hopeful Edmonton Protocol, whereby adult stem cells from donor cadavers are being used to produce pancreatic islets for transplant to treat diabetes. (I remember hearing about this back when I worked for a pharmaceutical company that made pancreatic enzymes.)
I mean, we've had promising results with adult stem cells - no ethical issues involved because adults can make an informed decision whether or not to donate their stem cells. Same story with cord blood - it hurts no one and is readily available and easy to collect. Once again, it's adults that can make the decision whether or not to donate the cord blood, and no lives or potential lives are threatened.
So, if I'm asked whether or not I support stem cell research, my answer is yes - I support research that uses adult stem cells and cord blood.
[ December 05, 2004, 01:43 AM: Message edited by: Belle ]
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