Kyoto University regrets to announce that Dr Susumu Tonegawa, a graduate of its Faculty of Science and honorary doctor, died on 11 July 2026.
Comment from the President
It is with profound sadness that I learned of the passing of Dr Susumu Tonegawa, a graduate of our Faculty of Science, an honorary doctor, and the first Japanese recipient of the Nobel Prize in Physiology or Medicine. On behalf of Kyoto University, I extend my heartfelt condolences to his family and colleagues.
After graduating in 1963, Dr Tonegawa moved to the United States to pursue advanced studies in molecular biology. He received his PhD from the University of California, San Diego in 1968, and subsequently devoted himself to elucidating the mechanisms of the immune system at the Basel Institute for Immunology in Switzerland and later at the Massachusetts Institute of Technology in the United States. There, he made the groundbreaking discovery of antibody gene rearrangement, for which he was awarded Japan's Order of Culture in 1984 and the Nobel Prize in Physiology or Medicine in 1987.
Thereafter, Dr Tonegawa continued his research in both Japan and the United States, expanding his work into the field of neuroscience. He achieved numerous breakthroughs, including explaining the nature of engrams (memory traces), thereby advancing our understanding of the mechanisms of memory. His enduring passion was to venture into unexplored fields of research, guided solely by his own intellectual curiosity and personal interest. Remaining at the forefront of science throughout his career, he inspired countless researchers of successive generations.
As a young researcher, I was fortunate to have many opportunities to discuss science with Dr Tonegawa. I still vividly remember being overwhelmed by the extraordinary passion and intensity that he brought to every discussion. More recently, for our 125th Anniversary Special Symposium in November 2022, he kindly sent us a heartfelt video message from Boston along with several other Nobel laureates associated with Kyoto University.
We are determined to carry forward Dr Tonegawa's aspirations by continuing to pursue research with the freedom, originality, and passion to boldly explore the unknown. On behalf of the faculty and staff of Kyoto University, I extend my heartfelt sympathies and condolences.
Nagahiro Minato
President, Kyoto University
16 July 2026
