Differential diagnosis of Hb EE and Hb E-beta(0)-thalassemia by protein and DNA analyses

DNA analysis was used to confirm the Hb EE genotype and to differentiate fr om the possible genotype of Hb E-beta(0)-thalassemia in two Malay patients. The first patient was a 13-year-old Malay girl, whose parents were availab le for family studies. The second patient was a 69-year-old Malay woman wit h no living family members. The presence of Hb E in both propositi was conf irmed by: (1) its characteristic electrophoretic mobilities on alkaline/aci d gels; (2) its chromatographic properties on anion/cation exchangers, and (3) its mildly insoluble properties. However, differential diagnosis of Hb EE and Hb E-beta(0)-thalassemia was challenging in these two cases. in the former, this was because of the possible interactions of the parents' pheno types; i.e,, the mother had a similar phenotype, In the latter, it was due to the lack of any living family members for family studies. In this commun ication, we present the protein and DNA analyses, including data on the use of the restriction enzyme MnI1, for the definitive diagnosis of the Hb EE genotype in the propositi of these two Malay families. Copyright (C) 2000 S . Karger AG, Basel.