美国国家公共电台 NPR Clinic Claims Success In Making Babies With 3 Parents' DNA(在线收听

 

STEVE INSKEEP, HOST:

A clinic in Ukraine has started making babies with DNA from three different people. They're doing this to help infertile women have children, but there are big concerns about so-called three-parent babies. NPR health correspondent Rob Stein went to Kiev to find out more. He is the first foreign journalist to be allowed inside the lab.

ROB STEIN, BYLINE: As I set out to find this three-parent baby clinic, even my taxi driver has a hard time finding it. Turns out the Nadiya Clinic is tucked away in a little side street on the outskirts of downtown Kiev. Nadiya means hope in Ukrainian. Dr. Valery Zukin runs the clinic.

Dr. Zukin?

VALERY ZUKIN: Yes.

STEIN: Hi. I'm Rob Stein. Nice to meet you.

ZUKIN: Yes. Nice to meet you.

STEIN: Zukin takes me to his office to explain why he's doing something so controversial.

ZUKIN: The patients with infertility came in the infertile clinic, and the doctors, they could see that the embryo stopped development at a very early stage.

STEIN: So these are women who are trying to get pregnant, and they...

ZUKIN: They never - they could not achieve the pregnancy, never.

STEIN: So Zukin decided to try something risky, a technique using DNA from three different people that was invented to help women carrying devastating genetic disorders have healthy babies.

ZUKIN: If you could help these families to achieve their own babies, why would it must be forbidden?

STEIN: To show me how it's done, Zukin sends me upstairs to the clinic's embryo lab to meet the clinic's embryologist, Pavlo Mazur.

PAVLO MAZUR: Nice to meet you.

STEIN: Nice to meet you, too.

Mazur takes a clear plastic dish out of an incubator and slides it under a big microscope. I can see what he sees on a big monitor. A big, round bubble comes into focus on the screen.

So what's that?

MAZUR: That's a one-day embryo.

STEIN: That's a one-day embryo right there, yeah.

The procedure starts with an egg from the woman trying to have a baby that's been fertilized to make a 1-day-old, single cell embryo.

MAZUR: That's single cell with two nuclei inside it. You see? One, and two. One is from sperm. It's paternal. And the second one is maternal.

STEIN: So that's the father's DNA and the mother's DNA. Right.

MAZUR: Right.

STEIN: A thin glass needle appears on the screen. Mazur slowly inserts the needle into the fertilized egg.

MAZUR: Very steady and slow.

STEIN: Why steady and slow?

MAZUR: We don't want to damage it, right? We want it to survive.

STEIN: He then uses the needle to extract the mother and father's DNA.

Wow. So that's - you just pulled out the DNA?

MAZUR: Yeah.

STEIN: So that's the mother's DNA and the father's DNA?

MAZUR: Yeah.

STEIN: And you just sucked it right out of there?

MAZUR: Yeah.

STEIN: Mazur does the same thing with a second fertilized egg, removes almost all the DNA. But this one, it was created from another woman paid to donate eggs.

MAZUR: And now we will just try to put the genetic material of our patient inside.

STEIN: I see. So the other one's been emptied out, and it's waiting for the patient's DNA?

MAZUR: Correct.

STEIN: Mazur gently inserts the needle into the donor's healthy egg and injects the genes of the couple trying to have a baby.

MAZUR: So you see it's inside.

STEIN: So that's the mother and father's DNA inside the donor egg?

MAZUR: Yeah.

STEIN: And it looks OK?

MAZUR: Yeah. It will develop into embryo.

STEIN: It worked?

MAZUR: Yeah.

STEIN: Wow. It's almost like a DNA transplant.

MAZUR: Yeah.

STEIN: The clinic's mostly treating Ukrainian women but is marketing this to women anywhere, charging those coming from other countries about $15,000. So far, the Nadiya Clinic doctors say, they've made four babies this way, and three more women are pregnant.

MAZUR: I adore that such technology exists. I adore that it can help some people.

STEIN: But these babies, they end up with a tiny bit of DNA left over from the woman who donated the egg. That DNA provides the egg's energy and may be what helps women finally get pregnant. That's why they're called three-parent babies. But Mazur says that label's wrong.

MAZUR: These babies, they have DNA from mother and from father. So they're genetically related to their parents, but a small, tiny part of DNA from donor. So it's incomparable. Your look, your hair color, your eyes color, your height, your weight and so on. These childrens are more like their parents, not donor.

STEIN: Some infertility doctors are welcoming this as a potentially exciting new option for some women. But critics are not.

MARCY DARNOVSKY: This is really an irresponsible kind of human experimentation.

STEIN: Marcy Darnovsky heads a genetics watchdog group called the Center for Genetics and Society. First of all, Darnovsky says, no one knows if this is safe.

DARNOVSKY: We just dont know whats going to happen to these children. This is pretty troubling.

STEIN: The procedure's banned in the United States. British doctors just started trying this, but only to prevent genetic diseases, and only one baby at a time as part of a tightly regulated research program. No one else is just selling it to treat infertility like the Ukrainian clinic. And that's not all, Darnovsky says.

DARNOVSKY: What we're seeing is a fast slide down a very slippery slope toward designer babies.

STEIN: That's because the DNA that's left over in the donated egg can be passed down by any girls to future generations. So Darnovsky worries this could open the door to making babies that are genetically modified for other reasons.

DARNOVSKY: Then we could see parents feeling eager to give their children traits like greater strength, need less sleep. Some people are saying that, yes, there are genes for IQ, and we can have smarter babies.

STEIN: Zukin says he's just trying to help desperate families have genetically related babies. And so far, he says, all the babies born this way appear to be perfectly healthy.

ZUKIN: It is a dream to have a genetical connection with the baby.

STEIN: Zukin says he's teamed up with a clinic in New York to start offering this procedure to American women willing to travel to Ukraine. Rob Stein, NPR News, Kiev.

  原文地址:http://www.tingroom.com/lesson/npr2018/6/437227.html