Departures of note

Susumu Tonegawa was born on September 5, 1939, in Nagoya, Japan. He studied at Kyoto University, graduating in 1963, and earned his Ph.D. at the University of California, San Diego in 1968. After post‑doctoral work at the Salk Institute, he joined the Basel Institute for Immunology, where his groundbreaking experiments on genetic recombination in B cells revealed the mechanism that generates antibody diversity. This discovery earned him the Nobel Prize in Physiology or Medicine in 1987, making him the first Japanese laureate in that category.

Following the Nobel award, Tonegawa shifted his research focus to neuroscience. He became a professor at MIT in 1981 and later directed the MIT Center for Learning and Memory, which evolved into the Picower Institute. His lab pioneered the use of transgenic and optogenetic techniques to study memory engram cells, demonstrating how specific neuronal ensembles store and retrieve memories. He also served as director of the RIKEN Brain Science Institute from 2009 to 2017.

Tonegawa resided in the Boston area with his wife, Mayumi Yoshinari Tonegawa, a former NHK director and freelance science writer. He was an avid Boston Red Sox fan and threw out an opening pitch during the team's 2004 World Series championship season. He died at his home in San Mateo, California, on July 11, 2026, at the age of 86.