Scientists Debate How Far To Go In Editing Human Genes : Shots - Health News The unusual meeting was called to consider a ban on certain uses of a new technique that can make precise changes in DNA. The main concern is altering genes in human sperm, eggs and embryos.

Scientists Debate How Far To Go In Editing Human Genes

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How far should scientists be allowed to go when they edit human DNA? That's the provocative question that was debated over the last three days at an unusual international conference in Washington, D.C. The conference came to a close this afternoon, and NPR health correspondent Rob Stein joins us now to talk about what happened. Rob, there's been a lot of talk about how this could be a historic meeting. Why is that?

ROB STEIN, BYLINE: Yeah, Robert. The meeting is called the International Summit on Human Gene Editing. And you know, I've been to a lot of scientific meetings over the years, and I was really struck at this meeting at how the sense of history really permeated the meeting. There's a real sense that scientists could be on cusp of taking an historic step that could have profound implications, profound benefits for society but also come with some equally profound dangers.

SIEGEL: Let's step back a little. What prompted this meeting?

STEIN: Yeah. You know, Robert, scientists have known how to do genetic engineering - you know, make changes in DNA - for decades. What's new is they recently developed some powerful new techniques that allow them to make really precise changes in DNA much more easily than ever before. So that's letting them make change that they could only dream of before.

SIEGEL: What kinds of things are they talking about trying to do?

STEIN: Well, there's a long list of things that they've already started to try to do using these new techniques. Most of them involve trying to find new ways to prevent and treat lots of diseases - everything from AIDS to cancer to Alzheimer's disease. But there's also some things they're doing that are making people very nervous.

And the one that's creating the biggest fuss, that was really the focus of this meeting, this summit, is that they've started to make changes in the DNA in human sperm, eggs and embryos. And that's something that always has been considered off-limits because this is the sort of DNA that's passed down for generations, you know, when people talk about passing on their genes to their children.

And so if you make changes in this DNA, it could become a permanent part of the human genetic blueprint and really, in some ways, could be seen as changing the course of human evolution. So you can see how the stakes suddenly get much higher.

SIEGEL: But describe why they would want to do that. And also, what's the danger in doing that?

STEIN: Absolutely. So during the summit, they talked about a lot of positive things that could come out of this. They could get some really important insights into human biology and human development, and they could also find ways to eradicate some terrible genetic diseases - you know, diseases that are passed down through families, like Tay-Sachs or Huntington's or Cystic Fibrosis. That's on the positive side.

On the negative side, one of the big concerns is they could simply make a mistake. This is very new science. They don't really know how to use it yet. And if they could make a mistake that results in new diseases, then that'd kind of mess up the human gene pool for generations.

SIEGEL: And other items on the negative side here?

STEIN: Yeah, there are. And one of the big ones is that, you know, if scientists do this for medical reasons, what's to stop them for doing it for other reasons, like, for example, to try to create what people call designer babies. You know, these are children that are smarter, taller, better athletes or something like that. Scientists are nowhere near being able to actually do that right now, but someday they might be able to. And if they let them do it for medical reasons, what's to stop them from doing it for other reasons? And that starts to conjure up all kinds of scary "Brave New World" images of, you know, genetically engineering a super race or something like that.

SIEGEL: So scientists from all over the world who engaged in these matters came to Washington, talked for three days. What's the outcome of it all?

STEIN: Yeah, so at the end of it after hearing about the science and the ethics and the legal issues that are raised both in the United States and internationally, the organizing committee issued a surprisingly specific statement. They said, very clearly, there's no way we're try to create a pregnancy or baby this way. It's just too dangerous and too unsafe. But they did strongly endorse doing the basic research in the laboratory to find out what's possible, what's safe and check in periodically as this proceeds to see if society has reached a consensus on whether we should take the next step or not.

SIEGEL: OK. That's NPR health correspondent Rob Stein. Rob, thanks.

STEIN: Thank you.

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