Sir John B. Gurdon (1933–2025)

Sir John Bertrand Gurdon, a developmental biologist whose work laid the foundation for stem cell research (Figure 1), passed away on October 7, 2025, at the age of 92.Best known for his landmark experiments demonstrating that the nucleus of a differentiated cell can be reprogrammed to support full development when transferred into an enucleated egg, Sir John's research established the conceptual basis for cloning and the later development of induced pluripotent stem cell technology.His discoveries, shared with Shinya Yamanaka, earned him the Nobel Prize in Physiology or Medicine in 2012.Sir John was born in Dippenhall, Surrey, England, and studied zoology at Christ Church, Oxford.After completing his doctorate, he held research and teaching