Coinheritance of beta thalassaemia (?0 Filipino) and delta variant (HbA2 Deventer) in Sabahan population: a case series

[66258_184734=] and heterozygous state of Codon 67 [GTG>ATG] Hb A2-Deventer mutation, NG_000007.3:g.[63512G>A][63512G=] (Figure 1 and 2). Detection of 5 unrelated cases of HbA2 Deventer may suggest that this delta variant is common among indigenous Sabahan. Since beta thalassaemia is also common in the population, more attention should be paid during diagnosis. Identification of delta variant in beta thalassaemia carrier is important because coinheritance of beta and delta thalassaemia results in a less elevated HbA2 level. Therefore, molecular testing of thalassemia carrier state in the case of borderline HbA2 is warranted to avoid misdiagnosis of beta thalassaemia carriers