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Major Embryonic Stem Cell Advance Raises Ethical Quandaries

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JEFFREY BROWN: And finally tonight, a major advance in stem cell work, but one that again raises ethical questions.

Researchers at Oregon Health and Science University were able to create embryonic stem cells through a cloned human embryo, a longtime goal, since such cells are capable of transforming into tissues and organs genetically identical to a patient who needs them.

Researchers took the DNA from a donor's unfertilized egg, then inserted mature skin cells containing the DNA of a patient. That led to the creation of an early-stage embryo called a blastocyst, a group of 50 to 100 cells. From that, scientists derived stem cells and then transformed them into heart cells.

The blastocyst was destroyed in the process and was never implanted in a human womb.

Rob Stein has been covering this story for NPR and joins us now.

Welcome to you.

ROB STEIN, National Public Radio: Nice to be here.

JEFFREY BROWN: So, first of all, why is this considered so important, this particular step?

ROB STEIN: Well, every since scientists discovered embryonic stem cell, one of the great dreams is that they would be able to use them to mass produce in the laboratory whatever kind of cell they want to treat patients, to be able to create thousands and thousands, millions of cells in the laboratory to be able to tailor-make cells to treat patients with -- let's say create brain cells to treat patients Alzheimer's or Parkinson's disease or create heart cells to treat patients who had heart attacks, or maybe cells for the pancreas for children with diabetes.

But in order to do that, they wanted to be able to tailor-make those cells with the genetic material of the patients they are trying to treat. And this is the technique that would finally be able to accomplish that goal.

JEFFREY BROWN: This has been hard to do, though, right? It's been a goal for a long time. What's the -- why so hard? Why the challenge?

ROB STEIN: That's right.

Scientists have been trying to do this for years. They have tried and tried and there's been failure after failure. There's been some claims that they did it that turned out to be fraud.

JEFFREY BROWN: Yes, a very notable one very recently, yes.

ROB STEIN: Yes, very high-profile.

JEFFREY BROWN: Yes.

ROB STEIN: And, for that reason, some scientists started to think that maybe it was impossible, that there was something about -- they could do it in mice and they could do it in monkeys and other animals, but they never were able to do it in humans.

And some scientists started to think maybe there is just something different about humans that made it impossible and that this wasn't -- we are never going to be able to achieve this goal.

JEFFREY BROWN: Is there a simple way to achieve to us what the -- what the difference was or what made it work?

ROB STEIN: Well, it seems like they were -- they basically tweaked the formula that they used to be able to do this.

And what -- as you said, they took the genetic material out of an egg and they replaced it with the genetic material from a cell. And there were a couple key steps that they did that seemed to make the difference. The first one was that they use very fresh eggs.

Many of the other attempts, they used eggs that were left over from fertility clinics. And that seems to be one key difference in this case. Another thing they did is, there was -- basically, they had to keep the egg at a certain stage of development, so that when they inserted the new genes, they had to do it at exactly the right moment, so that it would then be able to go on to develop into an embryo that could produce stem cells.

And it was that formula that seems to have made a difference. And it was very interesting. One of the aspects of that formula was caffeine.

JEFFREY BROWN: What we all take in every morning.

ROB STEIN: That's right.

JEFFREY BROWN: Now, what we were referring to that last time when it was announced by some Korean researchers, it turned out to be a hoax, right, or a ...

ROB STEIN: It was a fraud.

JEFFREY BROWN: A fraud. Yes. Yes. Yes.

ROB STEIN: It was a very high-profile case of scientific fraud.

JEFFREY BROWN: This time looks totally on the up-and-up and ...

ROB STEIN: Well, this is a very well-respected, well-known team of scientists out at Oregon Health and Science University. It has a long track record of having had success in doing this, using this technology in the laboratory.

As I said, they did it in mice, and then they did it in monkeys. And that seems to have been one of the keys is they had a lot of experience to be able to tinker with their formula to just get the right one that would work this time.

JEFFREY BROWN: Now, as we noted, this does raise concerns that we have talked about here, that you have reported for many years, including, of course, destroying human embryos.

ROB STEIN: Yes, it raises several ethical questions.

One of them is, as you said, the whole idea of intentionally creating and then destroying embryos in a laboratory for research purposes. And for people who believe that embryos basically have the same moral status as a human being, that's just morally repugnant and unacceptable.

Another ethical question that this raises is, they compensated the women financially for their eggs, which in many places is not permitted. There's only a couple of places in the country where they will do that, New York state and Oregon, because it raises all kind of questions about commodifying body parts, selling people's body parts.

And the last ethical concern this raises and probably the one that most people are concerned about is the technology they used is the same technology that was used to clone Dolly the sheep. So, some people think this basically could be a step towards human cloning, that they feel they will use the exact same techniques to possibly try to clone a human.

JEFFREY BROWN: So, it plays right into those fears that have been out there for a long time about cloning itself.

ROB STEIN: Right, right.

Now, the researchers who did this research say they don't think it would basically work, that whenever they have tried to do that with animals, it failed. And so they think it would fail if anybody tried to do that through people.

But there's a lot of concern that that might not stop somebody from at least trying.

JEFFREY BROWN: There is also the other part of the context here is the work that has been done with adult stem cells. Now, explain the difference if you can for us briefly, and why some think that's a better option for pursuit.

ROB STEIN: Yes.

We all carry around in our bodies adult stem cells. These are stem cells that could be turned into very specific tissues, like our hearts have heart stem cells and so they could be used to make new heart cells, but that's all they can do. They can't be used to be turned into brain cells, for example.

The big difference with embryonic stem cells is they could used to turn into any type of cell in the body. All 200 tissues in the body, an embryonic stem cell potentially could be used to make. Now, they have done some experiments with adult cells that seemed promising for certain diseases, like for heart disease perhaps. They use it for bone marrow transplants, for leukemia.

But the big difference here, as I said, is that embryonic stem cells are much, much more versatile.

JEFFREY BROWN: So where does this leave things, in our last minute here, in terms of the policy debate that continues? What happens next? And how does this newest development play into that?

ROB STEIN: Right.

Well, there's a lot of talk now that there might be an attempt to revive legislation in Congress to make cloning illegal in the United States, which it is not. Many other countries have made cloning illegal. In this country, it is still legal in most states. Maybe a dozen states have their own laws that make it illegal.

So, that may be a big debate, a political debate that comes up again in Congress. Last time that happened, it doesn't go anywhere because it got mired in the whole abortion debate. We will have to see if that happens again this time.

JEFFREY BROWN: All right, Rob Stein of NPR, thanks so much.

ROB STEIN: Oh, thanks for having me.


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