Geoff Yang

This year's Nobel Prize in Medicine went to controlling cells with light. Karl Deisseroth, Peter Hegemann and Georg Nagel, for optogenetics. Hegemann and Nagel found a protein in pond algae that opens a channel when light hits it. The algae use it to find light. In 2005 Deisseroth's lab put it into neurons. Now you can switch a single nerve cell on with a flash. In 2021 a blind man had the gene for one of these proteins delivered into cells in his retina. Wearing goggles that project the scene in amber light, he could find, touch and count objects on a table. That is the third Nobel for light and living cells. 2008: a glowing protein from a jellyfish, so you can see where one protein is. 2014: a way to see those glowing tags far more sharply than a light microscope should allow. 2026: an algae protein, so you can control a cell. All three start the same way. You put something into the cell that wasn't there: a jellyfish gene, a dye, an algae gene. Then you see or control the one thing you tagged. It sat for decades because the signal is so faint. The first spectra took hours to days to record. In 2008 a Harvard lab built a laser version sensitive enough for living tissue. By 2010 they had made it more than 1,000 times faster, fast enough for video. Then AI. A Raman image holds a full chemical spectrum at every pixel, far too much for a person to read. In 2024 a team at MIT and the Broad Institute trained a model to predict which genes a living cell has switched on from its Raman image alone, and followed the same cells for days. The standard way to read genes kills the cell. Writing to cells with light won this year. Reading them with light, with nothing added, is what we build at Precigenetics: chips that keep human cells alive under the laser, so the same cells can be read again and again while a drug acts on them.