[1] Brigham and Women's Hospital,Division of Hematology, Department of Medicine
[2] Harvard Medical School,Department of Pathology
[3] Broad Institute of MIT and Harvard,Department of Biology
[4] Brigham and Women's Hospital,undefined
[5] Harvard Medical School,undefined
[6] Howard Hughes Medical Institute,undefined
[7] Massachusetts Institute of Technology,undefined
[8] Current address: Institute of Experimental Hematology,undefined
[9] Hannover Medical School,undefined
[10] Hannover,undefined
[11] Germany.,undefined