Yogurt drink instead of a colonoscopy? CRISPR bacteria are tested

Dan Worthley, a gastroenterologist and cancer scientist at Colonoscopy Clinic in Brisbane, Australia, does thousands of colonoscopies a year, seeking and destroying precancerous polyps. It’s a practically surefire way to prevent colorectal cancer, but an unpleasant experience for patients. The future, Worthley hopes, will be much less onerous — and he’s developing a technology that, if it works one day, might make the experience more of a piece of cake.

Or, rather, a cup of yogurt — containing engineered bacteria that can detect and deliver a treatment for colorectal polyps or cancer. Worthley and colleagues at the University of California, San Diego, and the University of Adelaide published results in Science on Thursday that show they are one step closer to that far-off dream. In their paper, the researchers show a proof-of-concept engineered bacterium that can detect cancer DNA in the guts of mice and react to it by turning on certain cellular circuitry.

“I think it’s really cool. It introduces a new concept for how you can use cells as a sensor for something happening inside other cells,” said Mikhail Shapiro, a chemical and medical engineer at the California Institute of Technology who did not work on the study. “That can flip a switch inside those cells. In this case, it’s used for diagnostic output, but in principle it could be used for other things.”