Novel Βeta (β)-Thalassemia Mutation in Turkish Children

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 the beta chains of hemoglobin. 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 2 months to 16 years 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.