Hemoglobin Dieppe (HBB:c. 383A > G): A Rare Dominant β-Thalassemia in an Iraqi Kurdish Family.

Abstract

Dominant β-thalassemia is a rare form of thalassemia that is caused by a heterogenous group of molecular defects, including missense, nonsense, and frameshift mutations. Among the missense mutations involving the third exon of β-globin gene is the rare Hb Dieppe (HBB:c. 383A > G) which leads to a very unstable β-variant. In the current study we report this variant in an 8-year-old girl and her 35-year-old mother in an Iraqi Kurdish family, both presenting as β-thalassemia intermedia with moderate hypochromic anemia, increased hemoglobin F and borderline hemoglobin A2. This constitutes the first report of this variant from an Eastern Mediterranean country, and underscores the pivotal role of molecular studies to diagnose Hb Dieppe and other dominant β-thalassemias, since in most cases the resultant variants are undetectable by hemoglobin electrophoresis.