β-Thalassemia (β-thal) is a common autosomal recessive disorder resulting from over 300 different mutations of the β-globin genes. Our aim was to create a mutation map of β-thal in the province of Antalya, Turkey. In this study, mutation analysis of a total 146 of β-thal patients followed at the Thalassemia Center of the Antalya Education and Research Hospital, Antalya, Turkey, were included. Direct DNA sequence analysis was performed for mutation scanning of the β-globin gene. One hundred and forty-six patients with β-thal including all types were analyzed, and 14 different β-thal mutations were detected. The most frequently seen mutation was HBB: c.93 - 21G > A [IVS-I-110 (G > A)] (52.7%), followed by HBB: .c.92 + 6T > C [IVS-I-6 (T > C)] (14.4%), HBB: c.-80T > A [-30 (T > A)] (8.2%), HBB: c.315 + 1G > A [IVS-II-1 (G > A)] (8.2%), which made up 83.1% of the observed mutations. Our results indicate the importance of micromapping and epidemiology studies of thalassemia, which will assist in establishing the national prevention and control program in Turkey.
Keywords: mutation spectrum; non-transfusion-dependent thalassemia (NTDT); transfusion-dependent thalassemia (TDT); β-Globin gene; β-thalassemia (β-thal).