Combined heterozygosity for hemoglobin Paksé, α-thalassemia and for hemoglobin E, β- thalassemia ̵ first appearance in Europe

Abstract

Hemoglobinopathies are among the most common inherited diseases and they are believed to be one of the major etiologic factors contributing to anemia. Thalassemia is characterized by an altered hemoglobin (Hb) chain synthesis and may appear as alpha-(α-)thalassemia and/or beta-(β-)thalassemia. The clinical manifestations of thalassemia may range from asymptomatic to severe, with the potential to ultimately result in death. The search for an underlying cause was prompted by the discovery of an asymptomatic patient of Thai origin with microcytic anemia and no iron deficiency during a routine hematological examination. Genetic sequencing results revealed Hb Paksé, α2 CD 142 [A > T] (HBA2:c.429 A > T) and HbE β2 CD 26 [G > A] (HBB: c.79 G > A). It is essential that the identification and knowledge of Hb mutations facilitate the clinical recognition, genetic testing, and counseling of patients with thalassemia. The combination of two thalassemia Hb variants, one in the α-globin gene as Hb Paksé and one in β-globin gene as Hb E, in a single individual is occasionally described in East Asia. The first appearance of combined heterozygosity for Hb Paksé, and Hb E in Europe provides evidence that this is the result of a migration-caused occurrence.