title: Thalassemia intermedia associated with the Hb Constant Spring EE Bart's disease in pregnancy: a molecular and hematological analysis.
abstract: We defined the molecular basis and analyzed hematological phenotype associated with an unusual form of thalassemia intermedia caused by interaction of the hemoglobin Constant Spring (Hb CS), homozygous Hb E and alpha degrees -thalassemia found in two unrelated pregnant Thai women. Both patients had moderate anemia and characteristic of thalassemia intermedia. Hb-HPLC analysis demonstrated in both cases, Hb E and Hb Constant Spring with 3-4% Hb Bart's. Hb F was marginally elevated (3-5%). Both of them were diagnosed hematologically as the Hb CS EE Bart's disease. DNA analysis revealed the homozygosity for Hb E in both cases and identified the Hb CS mutation in trans to the alpha degrees -thalassemia allele with the SEA deletion in one case and with the Thai deletion in another. The appearance of Hb-HPLC peak resembling the Hb CS in peripheral blood of the two cases indicated the ability to form a tetrameric Hb molecule between alpha(CS) and beta(E) chains leading to a hybrid Hb namely the Hb E-CS (alpha2(CS)beta2(E)) with similar characteristics to Hb CS (alpha2(CS)beta2(A)). Hematological data of the patients were presented comparatively with other forms of related disorders in our series including 2 Hb H/Hb EE diseases, 16 homozygous Hb CS with and without Hb E, 14 Hb H diseases and 35 Hb H-CS diseases. Different genotype-phenotype correlations observed in these Thai patients with these disorders are illustrated.
authors.affiliation: Centre for Research and Development of Medical Diagnostic Laboratories (CMDL), Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, 40002, Thailand. supan@kku.ac.th
authors.forename: Supan
authors.initials: S
authors.lastname: Fucharoen
authors.forename: Goonnapa
authors.initials: G
authors.lastname: Fucharoen
authors.forename: Nattaya
authors.initials: N
authors.lastname: Sae-ung
authors.forename: Kanokwan
authors.initials: K
authors.lastname: Sanchaisuriya
mesh_terms: D004252:DNA Mutational Analysis; D005260:Female; D005838:Genotype; D006454:Hemoglobins / Q000032:analysis; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006801:Humans; D010641:Phenotype; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000175:diagnosis* / Q000235:genetics; D013785:Thailand; D013789:Thalassemia / Q000175:diagnosis* / Q000235:genetics
chemical_list: D006454:Hemoglobins; D006455:Hemoglobins, Abnormal; C030448:hemoglobin Bart's; C035541:Hemoglobin Constant Spring