Molecular and haematological characterization of compound Hb E/Hb Pyrgos and Hb E/Hb J-Bangkok in Thai patients

We describe haematological and DNA characterization of haemoglobinopathies in Thai adolescents caused by compound heterozygosities for Hb E [beta 26(B8) Glu-Lys] and two other beta-globin chain variants, Hb Pyrgos [beta 83(EF7) Gly-Asp] and Hb J Bangkok [beta 56(D7) Gly-Asp]. Hb analysis demonstrated that although these two beta-chain variants have separated elution profiles on liquid chromatography-based Hb analysis, they have similar alkaline electrophoretic mobilities on cellulose acetate electrophoresis. Haematological data associated with these two previously undescribed conditions were compared with those of pure carriers of the variants found in other unrelated Thai individuals. beta-Globin gene haplotypes linked to these two beta-chain variants and a simple DNA testing based on multiplex allele-specific polymerized chain reaction for differential diagnosis are presented.