Nobel Prize for Optogenetics Pioneers Deisseroth, Hegemann

The 2026 Nobel Prize in Physiology or Medicine was awarded to Karl Deisseroth, Peter Hegemann, and Georg Nagel for developing optogenetics, a method to control nerve cells with light. The prize recognizes the foundational work that created a switch for neural activity, a tool that has since defined a new era in brain research.

Foundational discoveries in light-sensitive proteins

Peter Hegemann studied how the single-celled alga Chlamydomonas swims towards light. He discovered that a light-sensitive protein is key to this light-directed movement. In the 2000s, Hegemann teamed up with Georg Nagel, who was then at the Max Planck Institute for Biophysics in Frankfurt, Germany. Together, they showed that the light-sensitive protein acts as a switch, opening a channel for ion flow when exposed to light. They named the protein channel-rhodopsin.

Karl Deisseroth of Stanford University, California, figured out how to turn this discovery into a tool for neuroscience. He genetically engineered rats to produce channel-rhodopsin in their nerve cells. This allowed those specific nerve cells to be activated simply by shining light on them. Deisseroth's key work was published in 2005.

Impact and ongoing applications of optogenetics

The 2005 breakthrough enabled researchers to study the function of specific groups of neurons with unprecedented precision. Since then, more light-sensitive proteins have been discovered that respond to different colours of light. These enable even more precise control of engineered nerve cells.

Optogenetic therapies are now being developed to restore sight in people blind due to loss of retinal rod and cone cells. The approach involves making surviving retinal nerve cells respond directly to light, a process that requires patients to wear special goggles. Several clinical trials are ongoing using this approach to restore sight.

A significant downside of optogenetics is that light cannot penetrate far into the body. To overcome this limitation, several groups worldwide are developing equivalent neural control methods based on ultrasound or magnetism. The Karolinska Institutet stated that the laureates' discoveries have "laid the foundation of a new era in neuroscience." Several clinical trials are ongoing using optogenetics to restore sight in people blind due to loss of retinal rod and cone cells.