CRISPR 101: Curing Sickle Cell, Growing Organs, Mosquito Makeovers | Jennifer Doudna | Big Think

Well, CRISPR is an acronym that actually represents a sequence of DNA letters in the genomes themselves. It is found in bacteria, and it was interesting to scientists originally because it's a bacterial immune system, a way that bacteria can fight viral infection. But the CRISPR acronym has now become widespread in the media as an indication of a new technology for gene editing. And the story of how an adaptive immune system in bacteria was harnessed as a technology for gene editing is really part of what A Crack in Creation is about.

So, the CRISPR gene editing technology is a tool that scientists can use to change the letters of DNA in cells in precise ways. So, I like to use the analogy of a word processor on our computer. We have a document; you can think about the DNA in a cell like the text of a document that has the instructions to tell the cell how to grow and divide and become a brain cell or a liver cell or develop into an entire organism. And just like in a document, the CRISPR technology gives scientists a way to go in and edit the letters of DNA just like we might cut and paste text in our document or replace whole sentences, even whole paragraphs or chapters. We can now do that using the CRISPR technology in the DNA of cells.

So, we think about a technology that allows precise changes to DNA to be made. For scientists, this is sort of really a gift that allows research to proceed very quickly in terms of understanding the genetics of cells and organisms, but also provides a very practical way to solve problems. There's many that we could discuss, but I'll mention a couple that I think are particularly exciting.

So, in clinical medicine, the opportunity to make changes to blood cells that would cure diseases like Sickle Cell Anemia disease, where we've understood the genetic cause for a long time, but until now, there hasn't been a way to actually think about treating patients. And now, with this technology, it's possible, in principle, to remove stem cells that give rise to blood cells in a person's body, make edits to those cells that would correct the mutation causing Sickle cell disease, and then replace those cells to essentially give a patient a new set of cells that don't have the defect. So, I think that's very exciting, and there are multiple research groups right now working on doing just that.

I think that's a future; probably sometime in the next two to five years, we will see clinical trials in that area, and we hope for real progress toward curing that disease. But another example that I think is also potentially very impactful clinically—but it has a very different kind of strategy—is the idea of making edits to pigs to create animals that are going to be better organ donors for humans. And so pigs are already of interest for organ donation, but imagine that we could make edits to the DNA of pigs to make their organs more human-like and also to remove any viruses from pig cells that might otherwise infect a patient. Those are both things that are actively underway using the CRISPR technology.

Then a third area that I think is interesting to think about from the perspective of global impact in disease is using gene editing, not to change the DNA in people, per se, but actually to affect the kinds of insects that transmit disease to people. The idea here is that one could use a gene editor to create mosquitoes that would be unable to transmit viruses like a dengue virus or Zika virus by using a technique called gene drive that allows traits to be spread very quickly through a population using an efficient way of gene editing such as the CRISPR tool.

I think that's an opportunity that could have a very big impact in terms of global health but also requires, obviously, some very thorough vetting and discussion about the potential environmental impact. I think one of the aspects of this technology that's been very interesting to me personally is my own kind of personal growth through the last few years. I think when I started this research project, which actually began now almost...