High Hb A₂ β-Thalassemia Due to a 468 bp Deletion in a Patient with Hb S/β-Thalassemia

Abstract

We describe a case of Hb S/β-thalassemia (thal) involving a 468 bp deletion that removes the β-globin gene promoter but leaves the coding regions intact. This is the second report of this deletion, and our family study establishes that this deletion causes β⁰-thal with unusually high levels of Hb A₂ and Hb F. As with other genotypes involving deletions of the 5′ region of the β-globin gene, our patient had a mild form of Hb S/β-thal.

• Hb S/β-thalassemia (thal)
• Promoter
• Deletion