DETECTION OF COMMON BETA THALASSEMIA MUTATIONS AMONG EGYPTIAN PATIENTS
Abstract
Beta-thalassemia is one of most common autosomal recessive disorders worldwide. Populations in the Middle- East, Mediterranean region, Central Asia, Indian and Far East countries show high prevalence for thalassemia. It is also relatively common in populations of African descent. The highest incidences are reported in Cyprus, Sardinia, and South East Asia. In Egypt, the genetic information concerning the molecular defects in β- thalassemia has not yet been fully investigated. The current study aims to detect the most common β-globin gene mutations in Egypt among β-thalassemic patients by using PCR and reverse hybridization method in an attempt to estimate the incidence of β-thalassemia mutations, a step in an assessment strategy of β-thalassemia management. Thirty seven confirmed β- thalassemia Egyptian patients were included in this study (twenty three males and fourteen females, seventeen thalassemia major and twenty thalassemia intermediate patients). Nine β-globin mutations were found in this study. IVS 1-110 was represented by 34% of the studied alleles while IVS 1-6 was represented by 23.5%, IVS 1-1 was represented by 19%, Codon 27 was represented by 6.5%, IVS 2-848 was represented by 6.5%, IVS 2-745 was represented by 2.1%, IVS 2.1 was represented by 2.5%, Codon 39 was represented by 4% and IVS 1.5 was represented by 1.5%. β-globin mutation (IVS 1- 110[G>A]) was found to be the most common homozygous mutation while, β- globin mutation (IVS 1-110[G>A]/ IVS 1- 6[T>C]) was found to be the most common heterozygous mutation. β-globin mutations (IVS 1-110[G>A], IVS 1-6[T>C] and IVS 1-1[G>A]) were found in 76% of allelic mutations. . In conclusion, establishment of β-thalassemia mutations data base may be a step in managing the diseases by carrier detection, prenatal diagnosis in high risk families, and thus can provide a tool in the prevention strategy of β-thalassemiaReferences
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