When was the first human bone marrow transplant performed?

The first successful bone marrow transplant in a patient was performed in 1968 by a medical team including Robert A. Good and E. Donnall Thomas. Bone marrow transplantation later became a major treatment for leukemia and other blood disorders. The procedure works by replacing diseased blood-forming cells with healthy donor stem cells. E. Donnall Thomas received the 1990 Nobel Prize for developing the therapy.