1. Leukaemia Research Cytogenetics Group, Northern Institute for Cancer Research, Newcastle University, Newcastle-upon-Tyne, United Kingdom;
2. Clinical Trial Service Unit, University of Oxford, Oxford, United Kingdom;
3. Department of Paediatric Oncology, St James University Hospital, Leeds, United Kingdom;
4. Department of Haematology, Sheffield Children's Hospital, Sheffield, United Kingdom; and
5. Department of Paediatric Haematology/Oncology, John Radcliffe Hospital, Oxford, United Kingdom