A Newly Identified Deletion of 970 bp at the α-Globin Locus That Removes the Promoter Region of the α1 Gene

Abstract

The most common causes of α-thalassemia (thal) are deletions that remove a part, or one or both of the functional α-globin genes. These deletions cause diminished expression of the α-globin protein, which may result in relatively low hemoglobin (Hb) and/or mean corpuscular volume (MCV) values. We here report the identification of a 970 bp deletion in the α1-globin gene that encompasses the entire promoter region of the α1-globin gene and 26 bp encoding the 5′ end of the mRNA. Thus, the affected α1-globin gene is prone to be nonfunctional. We therefore nominated the newly identified deletion allele α−α^Δ970. The MCV values of four related carriers of the α−α^Δ970 allele were slightly lowered, consistent with the presence of three functional α-globin genes.

Keywords:

• α-Thalassemia (thal)
• α-Globin
• α1 Gene
• Promoter
• Deletion