Laboratory diagnosis of a compound heterozygosity for Hb Hekinan [alpha27(B8) Glu-Asp] and a deletional alpha-thalassaemia 2 in Thailand.

We report the haematological and molecular characterization of a previously undescribed condition of compound heterozygosity for haemoglobin (Hb) Hekinan [alpha27(B8) Glu-Asp] and a deletional alpha-thalassaemia 2 detected in a Thai individual. Hb analysis demonstrated that although this Hb variant co-migrates with Hb A on cellulose acetate electrophoresis and cation-exchange high-performance liquid chromatography (HPLC), the HPLC procedure using a weak cation-exchange material with polyaspartic acid could clearly differentiate the two Hb. The variant could then be confirmed using the polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) analysis of the amplified alpha1-globin gene.