Mutations on the α2-Globin Gene That May Trigger α⁺-Thalassemia

Abstract

In the present study, a total of 11 individuals with hypochromic microcytic anemia who did not reveal the most common α-thalassemia (α-thal) deletions or mutations, were subjected to more investigations by DNA sequencing of the α-globin genes. Seven novel nondeletional α-thal mutations localized on the α2-globin gene in the heterozygous state were identified. These mutations either corrupted regulatory splice sites and consequently affected RNA processing or created unstable hemoglobin (Hb) variants. The mutations described here produced globin gene variants that lead to amino acid changes in critical regions of the globin chain. The clinical presentation of most patients was a persistent mild microcytic anemia similar to an α⁺-thal. In the last decade, numerous α-globin mutations have been observed leading to an α-thal phenotype and these studies have been considered to be important as discussed here.

• α-Thalassemia (α-thal)
• α2-globin gene
• hypochromic microcytic anemia
• premature stop codon

Acknowledgements

The authors gratefully thank Dr. Henri Wajcman for his critical reading and excellent suggestions for improving the manuscript. We thank all our colleagues in the Molecular Department of Kariminejad-Najmabadi Pathology and Genetics Centre, Tehran, Iran, for valuable technical assistance and also appreciate the cooperation of the patients who took part in this study.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.