Unexpected Genotype in a Non-Transfusion Dependent Thalassemia Family

摘要

Non-transfusion dependent thalassemia (NTDT) is an inherited hemoglobin disorder characterized by an α/non-α globin chain imbalance of variable severity, resulting in a wide spectrum of clinical manifestations. The coinheritance of additional α genes with a betathalassemia heterozygous mutation has a well-known negative effect. Triplication or quadruplication alone are mostly found by chance, but the coinheritance with β mutations can worsen the very mild anemia to a more severe hematological and clinical phenotype causing NTDT, depending on the severity of beta mutations. We describe a case of a 38-year-old β-thalassemia trait, pregnant woman at 33 weeks of gestation with supernumerary α-globin genes and two β-globin defects.