1 Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California Keck School of Medicine, Los Angeles, CA, USA. desmith@usc.edu.
2 USC Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, USA. desmith@usc.edu.
3 Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California Keck School of Medicine, Los Angeles, CA, USA.
4 USC Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, USA.
5 Haematopoietic Stem Cell Biology Laboratory, MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.
6 Department of Paediatrics and MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.
7 Department of Haematology, Great Ormond Street Hospital for Children, London, UK.
8 Division of Epidemiology and Clinical Research, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota, MN, USA. spector@umn.edu.