1. Childhood Cancer Research Unit; Department of Women's and Children's Health; Karolinska Institutet; Karolinska University Hospital Solna; Stockholm; Sweden
2. Department of Paediatrics; University of Gothenburg; Gothenburg; Sweden
3. Clinical Genetics Unit; Department of Molecular Medicine and Surgery, and Centre for Molecular Medicine; Karolinska Institutet; Karolinska University Hospital Solna; Stockholm; Sweden
4. Departments of Medicine and Haematology; Karolinska Institutet; Karolinska University Hospital Huddinge; Stockholm; Sweden