β-Thalassemia mutations and hemoglobinopathies in Adana, Turkey: results from a single center study

INTRODUCTION: β-Thalassemia and hemoglobinopathies are common genetic disorders in Turkey and in this retrospective study our aim was to determine the frequency of β-thalassemia and hemoglobinopathies in Adana, which is one of the biggest cities located in the southern part of Turkey. MATERIAL AND METHODS: Data from 3000 individuals admitted to Seyhan Hereditary Blood Disorders Center in Adana were evaluated. The blood samples were collected into EDTA-containing tubes and hematological parameters were analyzed using an automatic cell counter. High performance liquid chromatography technique was used to determine the type of hemoglobin. Molecular screening of the β-globin gene was performed with β-Globin StripAssay. RESULTS: Of 3000 cases, 609 were diagnosed as β-thalassemia or hemoglobinopathy. We have found that the rates of occurrence of β-thalassemia and hemoglobinopathies are 13.46% and 6.83% respectively in this area. We have identified 18 different β-thalassemia mutations and three separate abnormal hemoglobins: HbS, HbD Los Angeles, and HbE. In molecular analyses, β-thalassemia gene mutations of IVSI.110 (G > A), codon 8 (–AA), IVSI.1 (G > A), IVSI.6 (T > C), –30 (T > A), IVSII.1 (G > A), codon 39 (C > T), codon 44 (–C), IVSI.5 (G > C), codon 5 (–CT), codon 8/9 (+G), IVSII.745 (C > G), codon 22 (7bp del), –101(C > T), codon 36/37 (–T), IVSI.15 (T > G), codon 6 (–A), –88 (G > A) were detected. CONCLUSIONS: Considering the high incidence of mutations that we have found, β-thalassemia and hemoglobinopathies still seem to be a public health problem in Adana.