Diagnostic algorithm for NTDT. *β-thalassaemia traits and related disorders include α0 and α+-thalassaemia by deletions and non-deletional β-thalassaemia mutations. -There are two main types of HbH disease: 1) deletional HbH due to deletions (-α-/-α) and; 2) non-deletional HbH disease caused by α0-thalassaemia and non-deletional mutation (--/αTα). -The common disorders associated with Hb variants include homozygous HbE, HbE/βthalassaemia and HbE with other variants such as HbE/HbS or HbE/HbC or HbE/HbD, HbS (Sickle), HbS/β-thalassaemia, homozygous HbC and HbC/βthalassaemia. These diagnoses can be confirmed using appropriate globin genotyping.