HBB and hemoglobin H disease: Certain subgroups of these non-sickling hemoglobinopathies lead to non-transfusion dependent thalassemia (NTDT), such as Hemoglobin H disease (HbH) or reduced expression of the beta globin genes, resulting in an imbalance of the alpha to beta globin chains, such as Hemoglobin E/beta thalassemia (HbE/β thalassemia) [11].