An Indonesian case of compound heterozygote for hemoglobin E and deletion C at nucleotide 391 of the β-globin gene

Abstract

Hemoglobin E (HbE), having the substitution of glutamic acid with lysine at the 26th amino acid residue on β-globin, is the most common mutation of the β-globin gene in South East Asia. A compound heterozygote of this mutation with another mutation in the β-globin gene leads to a severe hemolytic disease known as hemoglobin E/β-thalassemia disease, where repeated blood transfusions are needed. In an Indonesian girl showing severe anemia and high levels of HbF and HbA2/HbE, the sequences of the β-globin gene were analyzed using an automatic DNA sequencer. The results showed one allele had G to A mutation at nucleotide (nt) 232 which resulted in the substitution of glutamic acid with lysine at codon 26 resulting in HbE; in the other allele deletion C at nt 391 was identified. This is a case report of a compound heterozygote of HbE and a deletion of C at nt 391 in the β-thalassemia region which showed severe anemia.