Objective: To compare the efficacy of routine haematological tests and molecular analysis in the diagnosis of double heterozygous α- and β-thalassaemia. Methods: Screening was carried out in extended family members from 125 families registered in the National Thalassaemia Registry, known to have both α- and β-thalassaemia carriers. Results: Eighty-three individuals from 59 families were identified to be double heterozygous for α- and β-thalassaemia only upon molecular analyses. Among 40 married individuals, 1 was at 25% risk for having β-thalassaemia major children and 6 for having Bart’s hydrops pregnancies. Conclusion: Molecular analysis must be used for the accurate diagnosis of double heterozygous α- and β-thalassaemia for proper risk ascertainment, especially in regions with a high prevalence of both types of thalassaemia.

Keywords:
Double heterozygotes, αβ-Thalassaemia, Routine haematological testing, Molecular analyses, Mutations
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© 2003 S. Karger AG, Basel
2003
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