1. Departments of Biochemistry and Molecular Biology and of StatisticsThe Pennsylvania State University, University Park PA
2. Genetics and Molecular Biology Branch, Hematopoiesis SectionNational Institutes of Health, NHGRI Bethesda MD
3. Department of Biochemistry and Molecular BiologyThe Pennsylvania State University College of Medicine Hershey, PA
4. Hematology DepartmentSt. Jude Children's Research Hospital Memphis, TN
5. Children's Hospital of Philadelphia Philadelphia, PA
6. Departments of Biology and of Computer ScienceJohns Hopkins University Baltimore, MD
7. Laboratory of Gene RegulationWeatherall Institute of Molecular Medicine, Oxford University Oxford UK
8. Department of Hematology, Cambridge Institute for Medical ResearchUniversity of Cambridge Cambridge UK