Abstract
Copy number variations in α-globin genes are results of unequal crossover between homologous segments in the α-globin gene cluster that misalign during the meiosis phase of the gametogenesis process. Reduction or augmentation of α-globin genes leads to imbalance of α/β chains in hemoglobin tetramer and consequently attenuate or worsen the β-thal clinical symptoms, respectively. Multiplications in α-globin genes have been found in some populations, justifying unexpected severe phenotype of β-thal carriers. Unexpected severe phenotype in the family members may result from coexistence of extra α-globin genes, which is an important factor in the causation of thalassemia intermedia and major in heterozygous β-thalassemia. We described different multiplications in α-globin locus in an Iranian family with one, two or three extra α-globin genes (ααα/αα, αααα/αα and αααα/ααα). The excess α-globin gene/genes cause increment in β/α chain imbalance and leads to worsening pathophysiology and clinical severity of β-thalassemia carriers.
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May 16, 2020·International Journal of Laboratory Hematology·Pallavi MehtaMalay B Mukherjee
Mar 27, 2018·International Journal of Laboratory Hematology·S LiuD-Z Li
Apr 1, 2021·Journal of Genetic Counseling·Lauren J IsleyJaime Shamonki