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Everything You Need to Know About CRISPR Gene Editing’s Monster Year

The explosion of gene-editing methods is transforming medicine, agriculture, and possibly the future of the human species.
December 1, 2015

Muscle-bound beagles. Hornless cows. Better potatoes. Genetically modified human embryos.

Scientists and bioethicists are meeting at the National Academy of Sciences in Washington, D.C.

The last 12 months have been incredible ones for genetic engineering. That’s mostly due to a new technology called CRISPR—an easy, cheap, and very precise way to “edit” the DNA of living cells.

This week several hundred scientists and bioethicists are meeting at the National Academy of Sciences in Washington, DC, to debate one of the most charged questions raised by CRISPR: whether we should ever use it to correct disease-causing genes in people before they’re born.

That idea is called “germ-line” editing, because it involves changing the DNA in sperm, eggs, or embryos. One day, gene editing might be used to avoid terrifying genetic conditions like Huntington’s disease or muscular dystrophy. Or maybe, as critics fear, it will lead to armies of blue-eyed super-intelligent babies.

But designer babies aren’t the whole story, or even the most important part. Gene editing is racing ahead in several areas that people should be aware of. Here’s our guide to everything you need to know about gene editing, from MIT Technology Review’s own coverage over the last 12 months.

Rewriting humans: In March, MIT Technology Review was first to take readers inside the emerging science and debate over editing of human genes. Now the experts gathered in Washington will consider whether society should bar the technology’s use in people, at least for now.

At a meeting at the National Academy of Sciences, the inventors of CRISPR gene editing debate whether the technology should be used to alter human DNA.

Reshaping animals: To understand what gene editing is capable of, look no further than the way scientists are already changing familiar animals. The menagerie of genetically modified creatures already includes flies, worms, ferrets, and even beagles engineered in China to be extra muscular. One project worth paying attention to is the effort by a startup called Recombinetics to engineer dairy cows so they don’t have any horns. The first two cows produced in this way posed for their first photo shoot last month.

Engineering plants: Big Ag is tripping over itself to get involved in gene editing, and we know one reason why: no regulation. The GM crops we’re familiar with—such as corn made resistant to weed killers—are subject to expensive safety testing and approval processes because they contain genes from bacteria. But it looks as if gene-edited crops may escape regulation in the U.S. entirely if scientists stick to playing around with plant genes, as they did when they created a gene-edited potato. DuPont, one of the largest sellers of GMOs, thinks the first gene-edited foods will be on dinner tables within five years.

Patent wars: Given the world-shaping potential of CRISPR gene editing, it’s no surprise there’s a fight over who really invented it. One on side is the University of California, Berkeley, where biologist Jennifer Doudna and colleagues from Europe say it’s their invention. On the other is Feng Zhang of the Broad Institute of MIT and Harvard, who says no, he hit on the idea first: he has won patents on its use in human cells. Berkeley has asked the U.S. Patent Office to rule on who should really own the valuable patents on CRISPR.

Gene therapy: It’s still early days, but the ability to tweak DNA more precisely is going to revolutionize gene therapy, the idea of installing healthy, working genes in adults and children with devastating genetic diseases like hemophilia. It’s risky and difficult medicine—in part because viruses are used to move the new DNA into a person’s body. No gene treatment has ever reached the market in the U.S. But gene editing is changing things by expanding the tool kit researchers have to work with. That’s because the technology lets them delete or correct genes as well as add them more precisely. Companies predict that within two years CRISPR will see its first tests in humans.

Basic research: The most important consequences of CRISPR are the least attention-getting: the effects in university research labs. It just makes so many experiments so much easier to carry out. That’s starting to speed basic research on cancer and autism. One clear indicator: the exponential growth in publications on CRISPR during the last few years.

Environmental release: Last month, biologists in California created mosquitoes that not only resist malaria but spread this trait to other mosquitoes. Their technology, called a “gene drive,” is a way to install the gene-editing machinery in a living thing so that it will spread specific DNA every time it reproduces. The researchers involved hope to release such mosquitoes to end malaria, but plenty of people are worried about that idea. Once released, such changes to species could be hard to undo.

Democratizing genetic engineering: This one should keep you up at night. CRISPR is so accessible—you can order the components online for $60—that it is putting the power of genetic engineering into the hands of many more scientists. But the next wave of users could be at-home hobbyists. This year, developers of a do-it-yourself genetic engineering kit began offering it for $700, less than the price of some computers. The trend might lead to an explosion of innovation—or to dangerous, uncontrolled experiments by newbies. Watch out, world. 

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