Complex interactions of δβ hybrid haemoglobin (Hb Lepore-Hollandia) Hb E (β^{26 g→a}) and α⁺ thalassaemia in a Thai family

Haemoglobin Lepore-Hollandia is an extremely rare condition in which a small deletion gives rise to a δβ hybrid, β-like globin. There are two single reports of patients from South Pacific Islands and Bangladesh. We describe a family from central Thailand, in which this Hb Lepore-Hollandia interacts with a common β globin variant (β^E resulting from the codon 26, G→A mutation) and α⁺ thalassaemia (-α^3.7). This intriguing interaction caused a troublesome diagnosis, as the two proband brothers were diagnosed as having Hb E/β thalassaemia. Molecular analysis of genomic DNA performed in this study allowed the definitive diagnosis of this complicated interaction. Such studies are required in the diagnosis of thalassaemia and haemoglobinopathies for particular regions like South-east Asia, where many different genotypes may give rise to haemoglobin disorders.