1. Division of Chemical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
2. Department of Surgical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
3. Division of Chemical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University and the National Health Laboratory Service, Cape Town, South Africa
4. Department of Immunology, School of Medicine, College of Health Sciences, Moi University, Eldoret, Kenya
5. Division of Endocrinology, Department of Medicine, Faculty of Medicine and Health Sciences Stellenbosch University, Cape Town, South Africa
6. Centre for Statistical Consultation, Stellenbosch University, Stellenbosch, South Africa
7. Division of Human Genetics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
8. Division of Human Genetics, National Health Laboratory Service, Universitas Hospital, Bloemfontein, South Africa