Thalassemic Mutations in Southern Iran

Background: approximately 180 mutations have been describedin (beta)-thalasselllia worldwide with specific spectrum ineach ethnic population, this study determines the spectrumand the frequency of (beta)-thalasselllia mutations in patients with(beta)-thalassemia trait and sickle cell-bvthalassemia.methods: fifteen compound heterozygous sickle cell thalassemia(sct) and 23 (beta)-thalassemia trait patients were studiedusing reverse dot blot, denaturing gradient gel electrophoresisand direct genomic sequencing,results: we detected distinct (beta)-thalassemia alleles in 15 compoundheterozygous of sct and 23 (beta)-thalassemia trait patients,the most common mutation was iysll-l(g(right arrow)a), foundin 15 of the 38 thalassemia chromosomes. iysil.l (g(right arrow)a) mutationis a single nucleotide change of g to a at interveningsequence 2 position 1 of (beta)-globin gene, detected in 11 out of23 chromosomes in a/(beta)-thalassemic patients and in four out of15 chromosomes of set patients. this mutation constitutedabout 39% of the mutations in both groups. the -25bp 3 iysi,deletion of 25 base pairs from 3' end of intervening sequence 1of (beta)-globin gene, was found to be the second prevalent mutationamong all chromosomes.conclusion: defining thalassemia mutations are necessary toestablish prenatal diagnosis programs leading to lower medicalcost. amongst 10 different types of mutation detected in (beta)thalassemicpatients from south of iran, two mutations ofiysli-l (g(right arrow)a) and -25bp 3 iysi were the most predominant(beta)-thalassemicalleles.