A compound heterozygous −29 A>G and IVS-I-1 G>A mutation of HBB gene leading to β-thalassemia intermedia in a Syrian patient: A case report

Abstract

Beta-thalassemia (β-thal) is an inherited hemoglobin disorder, characterized by the absence of or reduced hemoglobin chains that result in microcytic hypochromic anemia. In this case, we describe a patient case originating from Syria, and his hematology data were (Hb A1 = 12.5%, Hb F = 83.7, Hb A2 = 3.8%). The molecular analysis based on direct sequencing of the β-globin gene showed a rare combined heterozygous IVS-I-1 (G>A) (HBB:c.92+1 G>A)/−29 A > G (HBB:c.−79 A>G) causing β°/β+ thalassemia intermedia. Polymerase chain reaction–restriction fragment length (PCR–RFLP) method revealed that the patient had a homozygous (TT) for Xmn-1 locus. Our result showed the presence of rare β-thal (−29 A>G) mutation associated with IVS-I-1 (G>A). Our finding suggests the presence of this mutation resulted from old migrations.

Keywords

• β-thalassemia (β-thal)
• rare mutations
• syria
• -29 a>g beta+
• thalassemia intermedia