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J Pediatr Genet 2023; 12(01): 016-022
DOI: 10.1055/s-0041-1728744
Original Article

BCL11A Polymorphism in Egyptian Children with β-Thalassemia: Relation to Phenotypic Heterogeneity

Nouran Y. Salah 
1   Department of Pediatrics, Faculty of Medicine, Ain Shams University, Cairo, Egypt
,
Heba G. A. Ali
1   Department of Pediatrics, Faculty of Medicine, Ain Shams University, Cairo, Egypt
,
Noha Bassiouny
2   Department of Clinical Pathology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
,
Lamya Salem
2   Department of Clinical Pathology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
,
Sara I. Taha
2   Department of Clinical Pathology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
,
Mariam K. Youssef
2   Department of Clinical Pathology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
,
Layla Annaka
2   Department of Clinical Pathology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
,
Noha M. Barakat
1   Department of Pediatrics, Faculty of Medicine, Ain Shams University, Cairo, Egypt
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Abstract

Fetal hemoglobin (HbF) is a potent genetic modifier of β-thalassemia phenotype. B-cell lymphoma 11A (BCL11A) gene results in significant silencing of HbF. The aim of this study was to assess the prevalence of different BCL11A genotypes among a cohort of Egyptian children with β-thalassemia and to correlate them to HbF and clinical severity score. Eighty-two children with β-thalassemia (aged 12.95 ± 3.63 years) were recruited from the Pediatric Hematology Clinic, Ain Shams University. They were divided based on the clinical severity of β-thalassemia into three subgroups: 20 mild (24.4%), 24 moderate (29.3%), and 38 severe (46.3%). Age, gender, age of diagnosis, initial HbF level, transfusion history, and history of splenectomy were assessed. Anthropometric measures, signs of anemia and hemosiderosis, and the severity score were determined. Laboratory investigations such as complete blood picture, ferritin, and single gene polymorphism genotyping of the rs11886868 were also performed. Our findings showed that 16 children had CC genotype (19.5%), 38 had TC genotype (46.3%), and 28 had TT genotype (34.1%) of the rs#. β-thalassemia children with TT genotype had significantly higher severity scoring than the other two groups (p < 0.001). Moreover, mean initial HbF was found to be lower in children with TT genotype followed by TC and CC genotypes (p < 0.001). Increased γ-globin expression associated with BCL11A gene polymorphism is associated with better clinical severity of β-thalassemia.

Keywords

BCL11A polymorphism - β-thalassemia - phenotypic heterogeneity


Publication History

Received: 23 December 2020

Accepted: 10 March 2021

Article published online:
01 June 2021

© 2021. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 

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