1. Sheffield Children's Hospital; Sheffield UK
2. Clinical Trial Service Unit; University of Oxford; Oxford UK
3. Great Ormond Street Hospital; London UK
4. John Radcliffe Hospital; Oxford UK
5. Leukaemia Research Cytogenetics Group; Northern Institute for Cancer Research; Newcastle University; Newcastle-upon-Tyne UK
6. University Hospital Wales; Cardiff UK
7. Department of Haematology; UCL Cancer Institute; London UK
8. University College Hospital; London UK