WIDE SPECTRUM OF MUTATIONS IN THE BETA-GLOBIN GENE CAUSING BETA-THALASSEMIA MAJOR IN SOUTHWEST IRAN

Background and aim: beta-thalassemia (b-thalassemia) is characterized by the reduced synthesis of the hemoglobin beta chain. nowadays, more than 200 disease-causing mutations in beta-globin (b -globin) gene have been identified. beta-thalassemia is the most common monogenic disease worldwide and one of the widespread hereditary disorders in iran. considering the vast spectrum of beta-thalassemia mutations, it has multi-ethnic population. the gene frequency of betathalassemia is high and varies considerably in each region. therefore, it is necessary to determine the frequency and distribution of beta-thalassemia mutations in different regions.materials and methods: in the present study, two hundred and two beta-thalassemia major patients were subjected for genomic dna extraction from whole blood. amplification and subsequent sequencing of the beta-globin gene has been made by specific primers.results: thirty mutations were found in 404 studied alleles. our results show that ivsii-1(g>a) with 21.3% (86.404 alleles) represents the most common mutation, followed by the four mutations namely cd36.37 (-t) (16%), ivsi-110(g>a) (17.8%), ivsi-5(g>c) (6.9 %) and cd5 (-ct) (5.2%), respectively.conclusion: our findings indicate that the khuzestan population possesses a wide variety of thalassemia allelic distribution. these results can be used as basis for prenatal diagnosis of beta-thalassemia, especially in the south west of iran