An abstract of the article "Myeloid Sarcoma Associated with Gene Marking of Hematopoietic Stem Cells in a Rhesus Macaque," by Ruth Seggewiss, Stefania Pittaluga, Rima Adler, Cole Ferguson, Elio F. Vanin, Patrick F. Kelly, Robert E. Donahue, Brian P. Sorrentino and Arthur W. Nienhuis is presented.