Return to Transcripts main page

CNN Live At Daybreak

What Are Stem Cells?

Aired July 18, 2001 - 07:17   ET

THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.
CAROL LIN, CNN ANCHOR: Just in this morning, Senator Bill Frisk, the only physician in the Senate, and a Republican, will announce his support, this morning, for federal funding of embryonic stem cell research -- obviously, very controversial.

CNN medical correspondent Elizabeth Cohen joins us here, with more about also an NIH study that has come out.

You got a preview of it, and it's supporting federal funding of stem cell research. What do you know?

ELIZABETH COHEN, CNN'S MEDICAL CORRESPONDENT: Actually, it doesn't really come down on whether there should be federal funding or not. What it looks at is which kind of stem cells research should go on, adult stem cells, the kind that aren't controversial, because it doesn't involve any destruction of embryos, or embryonic, which does involve destruction of embryos. And what they said is both are good, both are useful, and both deserve more research, more attention, and more time.

LIN: I think where we get lost in a lot of this is what exactly is a stem cell -- why is this debate going on -- and the difference between embryonic and adult.

COHEN: Exactly. It's so interesting to me because there's so much passion on both sides of this. It gets so much attention. And you know, polls show that a lot of Americans don't really know exactly what stem cells are. So if you keep watching you'll find out. What is a stem cell, and how do they make them?

(BEGIN VIDEOTAPE)

COHEN (voice-over): Just like human beings, stem cells start out as a sperm and an egg. The egg is fertilized in the laboratory.

By the day after fertilization, it splits into a two-celled embryo. The next day it's four cells, then eight cells.

By day six, the embryo is a multicell ball called the blastocyst. At this point in the embryo's life it's tiny, the size of the dot on an eye. It can either be implanted into a woman's womb, to start a pregnancy, or frozen, to start a pregnancy at a later time.

If the embryo is to be used for stem cell research, however, several hundred stem cells from inside the blastocyst are removed, which destroys the embryo.

The stem cells can then multiply indefinitely in the lab. Stem cells are essentially blank cells with no identity. In the lab, scientists treat the cells to make them specialized, to convert them, for example, into cardiac cells, liver cells, bone marrow cells, or pretty much any type of human tissue.

So how can that help someone who's sick? Let's say someone's spinal cord has been damaged. Doctors could take stem cells, convert them into nerve cells, and give an injection of healthy cells to repair the damage. The same principle applies to the heart: After a heart attack, some of the cardiac muscle dies; stem cells could be made into cardiac cells and then injected, healing the heart tissue.

This explains just one way to make stem cells, which is to take a leftover embryo from a fertility clinic. There are other sources of stem cells -- for example, aborted fetuses or umbilical cords. Doctors say each appears to have its own benefits, but that the fertility cells are especially interesting, because at just six days old, they may more easily convert to other types of body tissue, the name of the game when it comes to stem cell research.

(END VIDEOTAPE)

COHEN: Now again, this new NIH report is viewed as being very important because it weighs in on which is more crucial, embryonic or adult, and what it says is that both are very important and both deserve more research.

LIN: All right. So as President Bush makes this decision, as Congress holds hearings, how influential, how important is this report in any final decision then?

COHEN: Well, from a scientific point of view, it's very important because these are the nation's top scientists who are saying that both embryonic and adults are important. You can't just do adults. Everyone, in some ways, would love to do just adult stem cells because there's no controversy there. Using cells from bone marrow or from umbilical cords is not controversial because you don't destroy any embryos in the process. However, the NIH did not weigh in on the ethical debate. That will still rage. What the NIH said today really doesn't have anything to do with ethics. If you believe destroying an embryo is an immoral act, it doesn't really matter what benefits might come from it.

LIN: You're simply saying more research needs to be done.

COHEN: Exactly.

LIN: All right.

COHEN: On both types.

LIN: Right.

COHEN: On embryonic and adults. LIN: All right. Thanks so much, Elizabeth.

TO ORDER A VIDEO OF THIS TRANSCRIPT, PLEASE CALL 800-CNN-NEWS OR USE OUR SECURE ONLINE ORDER FORM LOCATED AT www.fdch.com