It has inspired many follow-on discoveries on immune checkpoints, regulatory lymphoid and myeloid cells, and the role of major histocompatibility complexes (MHC; Benacerraf, Dausset, and Snell, 1980 Physiology or Medicine), all of which play pivotal roles in the immunosuppression to and the tolerance of cancer. The gene discussed is HLA-C; the disease is cancer.