2020 Was a Breakout Year for Crispr

Between glimpses of a medical cure and winning science’s shiniest prize, this proved to the gene-editing technology’s biggest year yet.
A black bull with an overlay of gene sequences.
Illustration: Tracy J. Lee; Elena Lacey; Getty Images

It will be difficult to remember 2020 as anything other than the year Covid-19 drew the world to a socially distanced standstill. But while thousands of life scientists pivoted to trying to understand how the novel coronavirus wreaks havoc on the human body, and others transformed their labs into pop-up testing facilities, the field of Crispr gene editing nevertheless persisted. In fact, it triumphed. Here are five of the (mostly coronavirus-free) breakthroughs in the Crisprsphere that you might have missed in 2020.

1. Crispr takes on blood diseases

Last summer, doctors in Tennessee injected Victoria Gray—a 34-year-old sickle cell disease patient—with billions of her own stem cells that scientists in Massachusetts had reprogrammed with Crispr to produce healthy blood cells. The hours-long infusion made her the first American with a heritable disease to be treated with the experimental gene-editing technology. And it appears to be working.

This July, Gray celebrated a year of being symptom-free. In December, a team that includes researchers from the two companies that developed the treatment—CRISPR Therapeutics and Vertex Pharmaceuticals—published promising results from a clinical trial, which is also treating patients in Germany who suffer from a related disease called ß-thalassaemia. In both groups of patients, the treatment seems to be safe, and it so far has eliminated the need for regular blood transfusions. It’s still too soon to say how long the effects will last, so don’t call it a cure just yet. But the consequences could be huge. Sickle cell disease and ß-thalassaemia are among the most common genetic disorders caused by mutations to a single gene, affecting millions of people worldwide.

2. The stable of gene-edited animals grows

For thousands of years, humans have been modifying the DNA of our closest furry and feathered friends by breeding animals to produce the most desirable traits. With Crispr, one no longer has to wait generations to make significant genetic changes. This year, researchers welcomed a raft of world-first barnyard creatures. Among them are pandemic-proof pigs, whose cells have been edited to remove the molecular lock-and-key mechanism that a variety of respiratory viruses use to infect them, and chickens Crispr’d to make them impervious to a common bird disease caused by the avian leukosis virus.

In April, scientists at UC Davis birthed Cosmo, a black bull calf whose genome had been altered so that 75 percent of his future offspring—rather than the natural 50 percent—will be male. He’s the first Crispr knock-in bovine, and proof that one day making all-male beef herds might be possible. (Female beef cattle convert feed to protein less efficiently, so in theory, the approach could mean fewer animals on the land, making it a win both for ranchers and the environment.)

For years, the future of gene editing in agricultural animals has been uncertain, since the US Food and Drug Administration decided in 2017 to regulate changes made by Crispr and other molecular tools as animal drugs. But on December 21, the US Department of Agriculture, which (much more leniently) regulates similar changes made to crops, announced a proposal to take charge of overseeing gene editing in animals bred for food as well. The move, if it goes through, could make it much easier for breeders to bring Crispr’d cows, chickens, pigs, and sheep to market in the US.

3. Disease detectors hit the market

For the past few years, startups spun out of Crispr patent rivals UC Berkeley and the Broad Institute have been sprinting to develop commercial diagnostics without the need for expensive lab instruments. The idea is to use Crispr’s programmable gene-seeking capabilities to pick up bits of foreign genetic material—from a virus, bacteria, or fungus—circulating in a sick person’s bodily fluids, and deliver those results via something that looks like a pregnancy test. Tests made with disposable paper strips are cheap and can go into the field or into people’s homes, greatly expanding their reach.

The pandemic sped up the need for such tests. This summer, the FDA authorized two Crispr-based tests, both for detecting SARS-CoV-2. Boston-based Sherlock Biosciences received the green light for its test in May, and the Bay Area’s Mammoth Biosciences followed in August. It marked the first time the FDA has allowed a Crispr-based diagnostic tool to be used on patients. The tests still need to be analyzed in a lab, but they are faster than the standard method for detecting SARS-CoV-2, called PCR, which typically takes four to eight hours to run. The new tests return results in about one hour. Both companies are currently working toward versions of the test that can be conducted at home.

“Before the pandemic, there was a lot of general excitement about the potential of next-generation diagnostics to decentralize the testing industry, but there was still a lot of inertia,” Mammoth Bioscience CEO Trevor Martin told WIRED this summer. The coronavirus, he says, shocked the industry out of it. “Things that would have taken years are now things that must be done in months.”

4. Mitochondria join the genome-editing party

Crispr can make precise cuts to the genomes of pretty much any organism on the planet. But mitochondria—cells’ energy-producing nanofactories—have their own DNA separate from the rest of the genome. Until recently, this DNA-targeting tool couldn’t manage to make changes to the genetic code coiled inside them.

And unlike chromosomes, which you inherit from both parents, mitochondrial DNA comes only from your maternal side. Mutations in mitochondrial DNA can cripple the cell’s ability to generate energy and lead to debilitating, often fatal conditions that affect about one in 6,500 people worldwide. Up until now, scientists have tried preventing mitochondrial disease by swapping out one egg’s mitochondria for another, a procedure commonly known as three-person IVF, which is currently banned in the US.

But this summer, scientists in Seattle and Boston published a study showing they had discovered a way to harness a strange enzyme found in biofilm-forming bacteria to make precise changes to mitochondrial DNA. The work was led by David Liu, whose evolution-hacking lab at the Broad Institute and Harvard University has churned out a series of groundbreaking DNA-altering tools over the last few years. The new system has not yet been tested in humans, and clinical trials are still a long way off, but the discovery opens up another promising avenue for treating mitochondrial disease.

5. Crispr’s Nobel victory

Last but certainly not least, in October, the 2020 Nobel Prize in Chemistry was awarded to Emmanuelle Charpentier and Jennifer Doudna for Crispr genome editing. It was both a stunning choice (as a DNA-altering tool, Crispr has only been around for 8 years) and a completely expected one. Crispr has completely revolutionized biological research since its arrival in 2012; scientists have since published more than 300,000 studies using the tool to manipulate the genomes of organisms across every kingdom, including mosquitoes, tomatoes, King Charles Spaniels, and even humans. It’s cheap, fast, and easy enough for almost anyone to use. Today, scientists can order custom-made Crispr components with the click of a button.

The win also broke barriers of another sort. Doudna and Charpentier are the first women to win a Nobel Prize in the sciences together. And there had been much speculation about who the prize would actually go to, since credit for the creation story of Crispr is still a matter of hot debate (and litigation). “Many women think that, no matter what they do, their work will never be recognized the way it would be if they were a man,” said Doudna upon learning the news. “And I think [this prize] refutes that. It makes a strong statement that women can do science, women can do chemistry, and that great science is recognized and honored.” In other words, she continued, “women rock.” We couldn’t agree more.


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