1. Clinical Research Division; Fred Hutchinson Cancer Research Center; Seattle WA USA
2. Department of Pediatrics; University of Washington School of Medicine; Seattle WA USA
3. Keck School of Medicine; University of Southern California; Arcadia CA USA
4. Children's Oncology Group; Arcadia CA USA
5. Hematology and Blood and Marrow Transplant Program; Hospital Universitario Central de Asturias; Oviedo Spain
6. Department of Pathology; St. Jude Children's Research Hospital; Memphis TN USA
7. Department of Laboratory Medicine and Pathology; University of Minnesota Medical Center; Minneapolis MN USA
8. Carman and Ann Adams Department of Pediatrics; Division of Hematology/Oncology; Children's Hospital of Michigan; Detroit MI USA
9. Children's Hopital of Philadelphia; Philadelphia PA USA
10. Aflac Cancer Center and Blood Disorders Service; Children's Healthcare of Atlanta; Atlanta GA USA
11. Children's Mercy Hospitals and Clinics; Kansas City MO USA