Novel Βeta (β)-Thalassemia Mutation in Turkish Children.

Abstract

Beta (β)-thalassemia is the most frequently observed hereditary blood disorder in the world. It is characterized by deficiency of hemoglobin β-globin gene and is also a profoundly heterogeneous both at the molecular and clinical level. In the case of β-thalassemia, there is reduced (β(+) type) or absent (β(o) type) synthesis of thebeta chains ofhemoglobin. β-Thalassemia clinically occurs in three main forms: major, intermedia and minor according to requirement of transfusion. The objective of this study was to evaluate β-thalassemia mutations in 89 patients ranging from 2monthsto 16years of age, who enrolled to Medical School Research and Training Hospital, Gaziantep University. The direct DNA sequence analysis was performed for mutation scanning of β-globin gene. 89 children with β-Thalassemia including all types were analyzed, 16 different β-thalassemia mutations were detected. We have also identified a novel mutation (HBB.c.-80delT, rs397509430) in the promoter region (-30 TATA box) of β-globin gene, and clinical data of patient having novel mutation was given. The β-Thalassemia mutations were determined as β-Thalassemia major type in 42 patients (47.19%), β-Thalassemia intermedia in 4 (4.49%), β-Thalassemia minor in 43, (48.31%) patients. The most frequent mutation was IVS I-110 G>A, followed by IVS I-1 G>A, IVS I-6 T>C, IVS II-1 G>A, respectively.