Department of Paediatrics, Faculty of Medicine, University of Kelaniya, Thalagolla Road, Ragama, 11010, Sri Lanka. Department of Pharmacology, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka. Adult and Adolescent Thalassaemia Centre, Colombo North Teaching Hospital, Ragama, Sri Lanka. Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka. Department of Medicine, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka. Department of Paediatrics, Faculty of Medicine, University of Kelaniya, Thalagolla Road, Ragama, 11010, Sri Lanka. sachith.mettananda@kln.ac.lk. University Paediatrics Unit, Colombo North Teaching Hospital, Ragama, Sri Lanka. sachith.mettananda@kln.ac.lk.