1. Department of Pediatrics I, ALL-BFM Study Group, Christian-Albrechts University Kiel and University Medical Center Schleswig-Holstein, Kiel, Germany;
2. Section for Stem Cell Transplantation and Immunotherapy, Department of Medicine II, Christian-Albrechts University Kiel and University Medical Center Schleswig-Holstein, Kiel, Germany;
3. Department of Pediatric Oncology, Hematology and Immunology, University of Heidelberg and Hopp Children’s Cancer Center at Nationales Centrum für Tumorerkrankungen Heidelberg, Heidelberg, Germany;
4. Institute of Human Genetics, Medical School Hannover, Hannover, Germany;
5. Institute of Social Medicine and Epidemiology, University of Lübeck, Lübeck, Germany; and
6. Department of Transfusion Medicine, Cell Therapeutics and Hemostaseology, University Hospital, Ludwig Maximilians University Munich, Munich, Germany