Susumu Tonegawa returns to the U.S. and is appointed Professor at the Center for Cancer Research at the Massachusetts Institute of Technology in 1981. His team discovers a tissue-specific transcriptional enhancer in the immunoglobulin heavy chain gene and identifies, clones and sequences gene coding for the polypeptide subunits of the T cell receptors.

Susumu Tonegawa marries Mayumi Yoshinari in 1985.

Susumu Tonegawa joins the Salk Institute in 1969 as a postdoctoral fellow. He works under Renato Dulbecco to define the transcripts of SV40 during lytic infection and in transformed cells.

Susumu Tonegawa is awarded the Nobel Prize in Physiology or Medicin in 1987 for his discovery of the genetic principle for generation of antibody diversity.

Susumu Tonegawa enters graduate school of the Department of Biology of the University of California, San Diego. He works in the laboratory of Masaki Hayashi on his thesis project about the transcriptional control of phage lambda and receives his Ph.D. in 1968. He remains there as a postdoctoral fellow until 1969.

Susumu Tonegawa is born in Nagoya, Japan in 1939.

Susumu Tonegawa joins the Basel Institute for Immunology (now Roche Center for Medical Genomics) in 1971. He establishes his own research group which applies techniques of molecular biology, namley restriction enzymes and recombinant DNA to study immunology.

Susumu Tonegawa attends Hibiya High School in Tokyo. He becomes interested in chemistry.

Susumu Tonegawa's research group can explain the genetic origin of antibody diversity. It is generated by somatic recombination of the inherited gene segments and by somatic mutation.

Susumu Tonegawa is admitted to the University of Kyoto in 1959 and studies chemistry. He is facinated by molecular biology and reads papers by François Jacob and Jacques Monod. He pursues graduate studies in this field under supervision of Professor Itaru Watanabe, who adivises him to continue his education in the US.

Sasumu Tonegawa marries Kyoko Sakita in 1960. The marriage is divorced in 1985.