American Scientist

It was 2013 when my colleagues at Science started using the word "craze" to characterize geneticists' work on the CRISPR-Cas system, a craze that has not only sustained itself but grown significantly over the past four years. Researchers derived the CRISPR-Cas system, which stands for Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) and their Cas (CRISPR-associated) genes, from the immune system of bacteria: It allows them to perform a wide range of genome edits, including modifying genes in living cells and organisms.

That may one day make it possible for researchers to use CRISPR-Cas systems to treat the genetic causes of disease by editing mutations within the genomes of actual patients. But that's still years away, of course, because no matter how promising the CRISPR-Cas system is, it takes time for any new treatment or therapy to undergo the required safety and efficacy testing.

Still, that promise alone explains why there's a "craze."

Other researchers are using the CRISPR-Cas system to probe the function of genes previously characterized by other techniques that amplified or silenced gene expression. Turns out that some "CRISPR studies muddy results of older gene research," as Nature put it earlier this year, which is prompting even more researchers to stop what they are doing to join in the CRISPR craze, at least for long enough to make sense of their conflicting results.

The craze extends also to researchers who work on other organisms, too, such as those relevant to food production and agriculture. Though for Rodolphe Barrangou at North Carolina State University's Food, Bioprocessing and Nutrition Sciences Department, "craze" isn't the right characterization: Barrangou has been working on the CRISPR-Cas system for more than a decade.

Earlier this year, Barrangou gave a talk at the Research Triangle Park chapter of Sigma Xi, which I recorded. Going in, I had read our interview with CRISPR codiscoverer Emmanuelle Charpentier, our published critique of Eric Lander's controversial paper "The Heroes of CRISPR," how CRISPR has promise in so many areas, including for treating the common genetic disorder thalassemia, and what Sheila Jasanoff had to say to us about the accompanying ethical concerns of CRISPR and other gene-editing technologies. But I hadn't yet struggled through a technical paper on exactly how CRISPR works. I also re-read my colleague's cover story for Wired, checked out (and tried to ignore at least the snarky) #crisprfacts on Twitter (though some made me laugh), and saw too that not "any idiot" can do CRISPR: As another of my colleagues at Science discovered, one must at least have good laboratory skills.

Sure, I picked up the essence of how CRISPR works: "Repeats" in a CRISPR are bits of genetic code from past invading viruses—bacteriophages—and that those serve as a kind of memory bank for the bacteria, allowing their immune system to detect (and so fight) the bacteriophage the next time it comes around. Researchers can then use that system to target any bit of genetic code. But as far as the technical aspects for how the whole CRISPR-Cas system works, that was pretty much what I knew.

After Barrangou's talk, though, I had a thorough primer on the CRISPR-Cas system from someone with significant perspective, including Barrangou's own belief in the CRISPR-Cas system's promise. Here's his talk with accompanying slides included. And in the years to come, I'll be referring back to it, too, I'm sure—multiple times—as the CRISPR craze continues.