1. Discipline of Medical Biochemistry, School of Laboratory Medicine and Medical Science, College of Health Science, University of KwaZulu Natal, Glenwood, Durban 4041, South Africa
2. Discipline of General Surgery, School of Clinical Medicine, College of Health Science, University of KwaZulu Natal, Umbilo, Durban 4001, South Africa
3. Department of Human Biology, Medical School, Faculty of Health Sciences, Nelson Mandela University, Missionvale, Port Elizabeth 6065, South Africa