1. Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa
2. McKusick-Nathans Institute and Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
3. Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town 7505, South Africa
4. South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Research Unit, Cape Town 7505, South Africa
5. Division of Human Genetics, Faculty of Medicine, Pharmacy and Odontology, University Cheikh Anta Diop, Dakar P. O. Box 5005, Senegal
6. National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
7. Department of Haematology and Blood Transfusion, School of Medicine, MUHAS, Dar es Saalam P. O. Box 65001, Tanzania
8. Department of Research and Training, Shree Hindu Mandal Hospital, Dar es Salaam P. O. Box 581, Tanzania
9. Hopital du point G, University of Bamako, Bamako P. O. Box 333, Mali
10. Center for Human Genetics, College of Medicine and Health Sciences, University of Rwanda, Kigali P. O. Box 4285, Rwanda
11. Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
12. Brighton & Sussex Centre for Global Health Research, Brighton and Sussex Medical School, University of Sussex, Sussex, BN1 9RH, UK
13. Department of Population and Quantitative Health Sciences, Institute of Computational Biology, Case Western Reserve University, Cleveland, 44106 OH
14. Sydney Brenner Institute for Molecular Bioscience, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Private Bag 3, Wits 2050, South Africa