Jennifer Doudna: We can now edit our DNA. But let's do it wisely (2)
Genome engineering is actually not new, it's been in development since the 1970s.
We've had technologies for sequencing DNA, for copying DNA, and even for manipulating DNA. And these technologies were very promising, but the problem was that they were either inefficient, or they were difficult enough to use that most scientists had not adopted them for use in their own laboratories, or certainly for many clinical applications. So, the opportunity to take a technology like CRISPR and utilize it has appeal, because of its relative simplicity. We can think of older genome engineering technologies as similar to having to rewire your computer each time you want to run a new piece of software, whereas the CRISPR technology is like software for the genome, we can program it easily, using these little bits of RNA. So once a double-stranded break is made in DNA, we can induce repair, and thereby potentially achieve astounding things, like being able to correct mutations that cause sickle cell anemia or cause Huntington's Disease.
I actually think that the first applications of the CRISPR technology are going to happen in the blood, where it's relatively easier to deliver this tool into cells, compared to solid tissues. Right now, a lot of the work that's going on applies to animal models of human disease, such as mice.
The technology is being used to make very precise changes that allow us to study the way that these changes in the cell's DNA affect either a tissue or, in this case, an entire organism. Now in this example, the CRISPR technology was used to disrupt a gene by making a tiny change in the DNA in a gene that is responsible for the black coat color of these mice.
Imagine that these white mice differ from their pigmented litter-mates by just a tiny change at one gene in the entire genome, and they're otherwise completely normal. And when we sequence the DNA from these animals, we find that the change in the DNA has occurred at exactly the place where we induced it, using the CRISPR technology. Additional experiments are going on in other animals that are useful for creating models for human disease, such as monkeys.
And here we find that we can use these systems to test the application of this technology in particular tissues, for example, figuring out how to deliver the CRISPR tool into cells. We also want to understand better how to control the way that DNA is repaired after it's cut, and also to figure out how to control and limit any kind of off-target, or unintended effects of using the technology. I think that we will see clinical application of this technology, certainly in adults, within the next 10 years.
I think that it's likely that we will see clinical trials and possibly even approved therapies within that time, which is a very exciting thing to think about. And because of the excitement around this technology, there's a lot of interest in start-up companies that have been founded to commercialize the CRISPR technology, and lots of venture capitalists that have been investing in these companies. But we have to also consider that the CRISPR technology can be used for things like enhancement.
Imagine that we could try to engineer humans that have enhanced properties, such as stronger bones, or less susceptibility to cardiovascular disease or even to have properties that we would consider maybe to be desirable, like a different eye color or to be taller, things like that. "Designer humans," if you will. Right now, the genetic information to understand what types of genes would give rise to these traits is mostly not known. But it's important to know that the CRISPR technology gives us a tool to make such changes, once that knowledge becomes available. This raises a number of ethical questions that we have to carefully consider, and this is why I and my colleagues have called for a global pause in any clinical application of the CRISPR technology in human embryos, to give us time to really consider all of the various implications of doing so.
And actually, there is an important precedent for such a pause from the 1970s, when scientists got together to call for a moratorium on the use of molecular cloning, until the safety of that technology could be tested carefully and validated. So, genome-engineered humans are not with us yet, but this is no longer science fiction.
Genome-engineered animals and plants are happening right now. And this puts in front of all of us a huge responsibility, to consider carefully both the unintended consequences as well as the intended impacts of a scientific breakthrough. Thank you.
Bruno Giussani: Jennifer, this is a technology with huge consequences, as you pointed out.
Your attitude about asking for a pause or a moratorium or a quarantine is incredibly responsible. There are, of course, the therapeutic results of this, but then there are the un-therapeutic ones and they seem to be the ones gaining traction, particularly in the media. This is one of the latest issues of The Economist -- "Editing humanity." It's all about genetic enhancement, it's not about therapeutics. What kind of reactions did you get back in March from your colleagues in the science world, when you asked or suggested that we should actually pause this for a moment and think about it? Jennifer Doudna: My colleagues were actually, I think, delighted to have the opportunity to discuss this openly.
It's interesting that as I talk to people, my scientific colleagues as well as others, there's a wide variety of viewpoints about this. So clearly it's a topic that needs careful consideration and discussion. BG: There's a big meeting happening in December that you and your colleagues are calling, together with the National Academy of Sciences and others, what do you hope will come out of the meeting, practically?
JD: Well, I hope that we can air the views of many different individuals and stakeholders who want to think about how to use this technology responsibly.
It may not be possible to come up with a consensus point of view, but I think we should at least understand what all the issues are as we go forward. BG: Now, colleagues of yours, like George Church, for example, at Harvard, they say, "Yeah, ethical issues basically are just a question of safety.
We test and test and test again, in animals and in labs, and then once we feel it's safe enough, we move on to humans." So that's kind of the other school of thought, that we should actually use this opportunity and really go for it. Is there a possible split happening in the science community about this? I mean, are we going to see some people holding back because they have ethical concerns, and some others just going forward because some countries under-regulate or don't regulate at all? JD: Well, I think with any new technology, especially something like this, there are going to be a variety of viewpoints, and I think that's perfectly understandable.
I think that in the end, this technology will be used for human genome engineering, but I think to do that without careful consideration and discussion of the risks and potential complications would not be responsible. BG: There are a lot of technologies and other fields of science that are developing exponentially, pretty much like yours.
I'm thinking about artificial intelligence, autonomous robots and so on. No one seems -- aside from autonomous warfare robots -- nobody seems to have launched a similar discussion in those fields, in calling for a moratorium. Do you think that your discussion may serve as a blueprint for other fields? JD: Well, I think it's hard for scientists to get out of the laboratory.
Speaking for myself, it's a little bit uncomfortable to do that. But I do think that being involved in the genesis of this really puts me and my colleagues in a position of responsibility. And I would say that I certainly hope that other technologies will be considered in the same way, just as we would want to consider something that could have implications in other fields besides biology. BG: Jennifer, thanks for coming to TED.
JD: Thank you.