Scientists Urge Temporary Moratorium On Human Genome Edits

Mar 20, 2015
Originally published on March 20, 2015 7:58 pm

A new technology called CRISPR could allow scientists to alter the human genetic code for generations. That's causing some leading biologists and bioethicists to sound an alarm. They're calling for a worldwide moratorium on any attempts to alter the code, at least until there's been time for far more research and discussion.

It's not new that scientists can manipulate human DNA — genetic engineering, or gene editing, has been around for decades. But it's been hard, slow and very expensive. And only highly skilled geneticists could do it.

Recently that's changed. Scientists have developed new techniques that have sped up the process and, at the same time, made it a lot cheaper to make very precise changes in DNA.

There are a couple of different techniques, but the one most often talked about is CRISPR, which stands for clustered regularly interspaced short palindromic repeats. My colleague Joe Palca described the technique for Shots readers last June.

Why scientists are nervous

On the one hand, scientists are excited about these techniques because they may let them do good things, such as discovering important principles about biology. It might even lead to cures for diseases.

The big worry is that CRISPR and other techniques will be used to perform germline genetic modification.

Basically, that means making genetic changes in a human egg, sperm or embryo.

Those kinds of changes would be passed down for generations. And that's something that's always been considered taboo in science.

One major reason that it's considered off limits, ethically, is that the technology is still so new that scientists really don't know how well it works.

The fear is that mistakes could be made, causing some new disease by accident. That disease could then be passed down for generations.

Another concern is that this could open the door to what people call designer babies.

If you let someone manipulate the genes in an egg or embryo to prevent a disease, where would you draw the line?

People could use this, possibly, to make babies that are smarter, taller or better athletes. Hair and eye color could be manipulated. IQs could be boosted or lowered.

It raises all kind of Brave New World issues about genetically engineering the human race.

Moratorium gains momentum

In the last week or so, there's been a flurry of statements from several groups of scientists warning about all this. MIT's Technology Review had an in-depth report on the whole issue a couple of weeks back, if you want to learn more.

This week, groups that include the University of California's Jennifer Doudna, one of the researchers who developed CRISPR, essentially called for a moratorium on any attempt to do modification of the human germline using these techniques — at least until there's been more time for public discussion and more research to understand how well it works and how safe it is.

In interviews, several of the scientists and bioethicists issuing these statements said they are concerned things are moving too fast.

Last week, another group that includes some of the researchers who developed another gene editing technique, went even further and called for moratorium on doing any research in the laboratory that could lay the groundwork for attempting germline modification.

Not all scientists support this movement. Some say this powerful new technology is needed to advance science. It could produce important knowledge about stem cells, infertility — all sorts of things, they point out.

Still, there are concerns that rogue scientists could take information being published about such techniques and use the recipe in ways many people would find unethical — and dangerous.

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Leading biologists and bioethicists are sounding an alarm about new technology that could allow scientists to alter the human genetic code for generations. Researchers are calling for a worldwide moratorium on any attempts to do that. At least until there's been time for a lot more research and discussion. And NPR science correspondent Rob Stein joins me now to talk about this. Rob, let's start first by talking about the science involved. What exactly is it that's prompted this concern?

ROB STEIN, BYLINE: Well, Melissa, as you know, scientists have known for a long time how to manipulate human DNA, how to do genetic engineering, what they call genetic editing. But it's only been limited to really highly-skilled geneticists were the people who could do this because it was really hard, really slow and really expensive. But what's happened is scientists have developed some new techniques that make it much faster, much cheaper, much easier to make very precise changes in human DNA. And for that reason a lot more people can do it.

BLOCK: A lot more people can do it and that raises all sorts of ethical concerns, right?

STEIN: That's right. Scientists are really excited about this technology because they might be able to use it to do all sorts of good things and even perhaps to cure human diseases. The big worry is about something called germline genetic modification. And that involves changing the genes in a sperm, an egg or an embryo. And that's long been considered taboo in science - off limits.

BLOCK: OK, well, let's break that down a little bit - the germline genetic modification that you're talking about - and why specifically that raises kinds of problems.

STEIN: Well, there's a long list of concerns about that. The big one is that this is all very new and scientists really, really don't know how well it works yet or how safe it is. And they can make some kind of mistake and that can end up introducing some new disease into the human genetic blueprint that would be passed down for generations. Another concern is that this could open the door to what a lot of people call designer babies. Where if you let people do this, say, to cure disease, what's to stop them from trying to do this to make a baby that's smarter or taller or a better athlete? And that gets into this whole new "Brave New World" issue of, you know, genetically engineering the human race.

BLOCK: Now, we mentioned the worldwide moratorium that some are calling for - explain what that's about.

STEIN: Yeah, so over the last week there's been several groups of scientists who have issued statements about this, basically warning about this, including one that came out this week that included a scientist who developed that technique I mentioned earlier - CRISPR. And what they're saying is wait a minute. We need to take some time to really think about this, talk about it, do some more research and make sure it's safe and to air all these issues that it raises. Another group of scientists last week issued a similar statement in which they actually went a step further and said we should not only not let anybody try genetic modification on the human germline, we shouldn't even be doing the basic research in the laboratory on eggs and embryos that could lay the groundwork for doing this sort of thing in the future.

BLOCK: So there's some division among scientists on this question.

STEIN: Right, I spoke to several of these scientists today. And scientists in one group are saying look, this is really important technology and we should be able to use it in the laboratory to see what we could learn. It could provide lots of really important insights into human biology, cures for infertility, stem cell research. But another scientist I spoke with said look, if you do that and you let scientists do these experiments and publish them in the scientific literature, you're basically giving rogue scientists out there the formula to do exactly what we're all worried about.

BLOCK: Would a worldwide moratorium be enforceable in any way?

STEIN: That's a very good question, and, really, it would not be enforceable. In countries like the United States and in Europe there are regulatory bodies like the Food and Drug Administration that could prevent this sort of thing from happening. But the idea is that by issuing these statements, if we can create a scientific consensus, it would sort of have the moral authority to really persuade people not to even try this.

BLOCK: OK, NPR's Rob Stein. Rob, thanks so much.

STEIN: Oh, sure, nice to be here. Transcript provided by NPR, Copyright NPR.