Molecular Characterization and Disease-Related Morbidities of β-Thalassemia Patients from the Northeastern Part of Iraq

BACKGROUND: β-thalassemia is a significant problem in the northeastern part of Iraq, and has imposed a huge burden on the health authorities. OBJECTIVE: To identify the molecular characterization and morbidity prevalence in transfusion-dependent thalassemia (TDT) and non-transfusion dependent thalassemia (NTDT) phenotypes in northeastern Iraq. PATIENTS AND METHODS: This is a cross-sectional study conducted on 242 β-thalassemia patients from 162 families. Reverse hybridization technique and direct gene sequencing were used to characterize β-thalassemia mutations, and medical records of the patients were reviewed with a well-designed questionnaire. RESULTS: A total of 22 β-globin mutations arranged in 53 different genotypes were identified: IVS-II-1 (G> A) (35.7%), followed by IVS-I-6 (T> C) (18.0%), and codon 8/9 (+G) (8.5%) were the most frequent. Among disease-related morbidities, bone disease amounted to (66.9%), followed by endocrinopathies (32.2%), hepatobiliary complications (28.9%), and pulmonary hypertension (9.9%), whereas thrombosis, extramedullary hemopoiesis, and leg ulcers were less frequent. CONCLUSION: The overall complications rate was 78.9%, with a growing probability of complications with advanced age, with evidently higher rates in patients with β(0)β(0) and β(0)β(+) genotypes that explain the role of underlying genetic defects in the pathophysiology of disease complications.