Oct 5, 2026 —
The 2026 Nobel Prize in Physiology or Medicine has gone to Karl Deisseroth, Peter Hegemann, and Georg Nagel for the discovery of light-gated ion channels and the invention of optogenetics, a method that uses light to switch specific neurons on and off.
The tools trace back to channelrhodopsin, a protein from algae that senses light and moves ions across a cell membrane at the same time. Hegemann’s lab identified the first channel and Nagel’s team characterized a second, blue-light-activated one. Deisseroth then showed that placing it in mammalian neurons let researchers trigger activity with a pulse of light, first in cultured cells and later in the brains of living mice.
For gene and cell therapy, the relevant thread is delivery. Putting a light-sensing protein into surviving cells is a gene therapy problem, and in the retina it is typically solved with an adeno-associated virus (AAV) vector. Preclinical work used an intraocular AAV carrying channelrhodopsin to restore light responses in models of retinitis pigmentosa, and that approach has now reached patients.
