Investigating the Molecular Map of Transfusion Dependent and Non-Transfusion Dependent β-Thalassemic Patients in Baghdad City

Abstract

Background:    β-thalassemia syndrome (BT) is an inherited blood disorder characterized by reduced levels of functional hemoglobin owing to relative reduction or complete lack of β-globin chain synthesis. The severity of the BT phenotype relies highly on the underlying genetic defect affecting the β-globin gene. The high prevalence rate, as well as, the relatively high annual cost for thalassemia patients in Iraq, has imposed a huge burden exhausting both patients and the health institutions.
Objective:    To study the molecular profile of BT patients in Baghdad city with characterizing the most common β-globin gene mutation among transfusion dependent (TD) and non-transfusion dependent (NTD) patients.
Methods:    A cross-sectional study was conducted on 80 TD and NTD BT Patients. Molecular profiling of BT mutations was performed using β-Globin StripAssay®IME, a reverse-hybridization assay tailored to detect population-specific mutations within the Middle East, Iran, Arabian Peninsula, and India.
Results:    In the current study, 13 different BT mutations have been identified, of which 3 alleles accounted for approximately 60% of the total alleles. These were: intervening sequence (IVS) 1.110 {G>A} in 44 (27.5%), IVS 2.1 {G>A}: 35 (21.9%), and Codon 44 {-C}: 14 (8.8%). Other alleles were less frequent including IVS 1.6 {T>C}: 11 (6.9%), Codon 36/37 {-T}:10 (6.3%), while the remaining alleles accounted for 5% or less each.
Conclusion:    The  study has revealed a clustering of discrete BT alleles, indicated by the dominance of (IVS) 1.110 {G>A}, IVS 2.1 {G>A}, and Codon 44 {-C}:  alleles in nearly 2/3 of the studied subjects.
Keywords:    Molecular map, β-thalassemia, mutation, HBB gene, alleles
Citation:    Alaqidi AA, Al-Mamoori HS. Investigating the molecular map of transfusion dependent and non-transfusion dependent β-thalassemic patients in Baghdad City. Iraqi JMS. 2025; 23(2): 393-403. doi: 10.22578/IJMS.23.2.22