1. Department of Paediatrics College of Medicine University of Lagos Lagos Nigeria
2. Department of Paediatrics Lagos University Teaching Hospital Lagos Nigeria
3. Department of Medicine College of Medicine University of Lagos Lagos Nigeria
4. Department of Medicine Lagos University Teaching Hospital Lagos Nigeria
5. Central Research Laboratory College of Medicine University of Lagos Lagos Nigeria
6. National Human Genome Research Institute National Institutes of Health Bethesda MD USA
7. Cincinnati Children's Hospital Medical Center Cincinnati OH USA
8. Children's National Medical Center Washington DC USA