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2019. 4
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Scientists Control CRISPR With Light
Engineers show that near-infrared light can trigger the release of CRISPR-Cas9 to slow tumor growth
Engineers are making their mark on biotech’s hottest commodity. Chinese scientists today reported that they can control the gene editing tool CRISPR-Cas9 with light.
The method replaces the use of viruses traditionally used to deliver CRISPR gene editing machinery, and gives scientists temporal control over the tool, the researchers said. They published their findings in the journal Science Advances.
The technique has the potential to precisely target and kill cancer cells, says Yujun Song, an author of the paper and a professor in the College of Engineering and Applied Sciences at Nanjing University in China.
CRISPR—short for Clustered, Regularly Interspaced, Short Palindromic Repeats, is a genetic phenomenon found in microbes that scientists have turned into a DNA chopping machine. When combined with certain proteins, typically one called Cas9, the biological complex can cut and paste DNA, altering life’s genetic code.
Physically delivering CRISPR-Cas9 into a cell typically requires hitching the complex to a virus. The virus invades the nucleus of the target cell, delivering the CRISPR cut-and-paste machinery. The strategy works, but using viruses as a delivery method can cause problems, such as provoking cancer or an immune response.
Researchers have proposed several alternative delivery materials, including gold nanoparticles, black phosphorus, metal-organic frameworks, graphene oxide, and various nanomaterials. These methods avoid some of the pitfalls of viruses, but still don’t give scientists control over the timing of gene editing.
That’s where light comes in. The authors of the new report anchored CRISPR-Cas9 to light-converting nanoparticles using a light-sensitive chemical compound. Then, by exposing the particles to light, the scientists triggered the release of the CRISPR-Cas9 machinery from the nanoparticles, delivering them to cells on demand.
How IBM Watson Overpromised and Underdelivered on AI Health Care
After its triumph on Jeopardy!, IBM’s AI seemed poised to revolutionize medicine. Doctors are still waiting
In 2014, IBM opened swanky new headquarters for its artificial intelligence division, known as IBM Watson. Inside the glassy tower in lower Manhattan, IBMers can bring prospective clients and visiting journalists into the “immersion room,” which resembles a miniature planetarium. There, in the darkened space, visitors sit on swiveling stools while fancy graphics flash around the curved screens covering the walls. It’s the closest you can get, IBMers sometimes say, to being inside Watson’s electronic brain.
One dazzling 2014 demonstration of Watson’s brainpower showed off its potential to transform medicine using AI—a goal that IBM CEO Virginia Rometty often calls the company’s moon shot. In the demo, Watson took a bizarre collection of patient symptoms and came up with a list of possible diagnoses, each annotated with Watson’s confidence level and links to supporting medical literature.
Within the comfortable confines of the dome, Watson never failed to impress: Its memory banks held knowledge of every rare disease, and its processors weren’t susceptible to the kind of cognitive bias that can throw off doctors. It could crack a tough case in mere seconds.
If Watson could bring that instant expertise to hospitals and clinics all around the world, it seemed possible that the AI could reduce diagnosis errors, optimize treatments, and even alleviate doctor shortages—not by replacing doctors but by helping them do their jobs faster and better.
Outside of corporate headquarters, however, IBM has discovered that its powerful technology is no match for the messy reality of today’s health care system. And in trying to apply Watson to cancer treatment, one of medicine’s biggest challenges, IBM encountered a fundamental mismatch between the way machines learn and the way doctors work.
IBM’s bold attempt to revolutionize health care began in 2011. The day after Watson thoroughly defeated two human champions in the game of Jeopardy!, IBM announced a new career path for its AI quiz-show winner: It would become an AI doctor. IBM would take the breakthrough technology it showed off on television—mainly, the ability to understand natural language—and apply it to medicine. Watson’s first commercial offerings for health care would be available in 18 to 24 months, the company promised.
In fact, the projects that IBM announced that first day did not yield commercial products. In the eight years since, IBM has trumpeted many more high-profile efforts to develop AI-powered medical technology—many of which have fizzled, and a few of which have failed spectacularly. The company spent billions on acquisitions to bolster its internal efforts, but insiders say the acquired companies haven’t yet contributed much.
And the products that have emerged from IBM’s Watson Health division are nothing like the brilliant AI doctor that was once envisioned: They’re more like AI assistants that can perform certain routine tasks.
“Reputationally, I think they’re in some trouble,” says Robert Wachter, chair of the department of medicine at the University of California, San Francisco, and author of the 2015 book The Digital Doctor: Hope, Hype, and Harm at the Dawn of Medicine’s Computer Age (McGraw-Hill). In part, he says, IBM is suffering from its ambition: It was the first company to make a major push to bring AI to the clinic. But it also earned ill will and skepticism by boasting of Watson’s abilities. “They came in with marketing first, product second, and got everybody excited,” he says. “Then the rubber hit the road. This is an incredibly hard set of problems, and IBM, by being first out, has demonstrated that for everyone else.”
