Optimal strategies for carrier screening and prenatal diagnosis of α- and β-thalassemia.

The thalassemias are inherited quantitative disorders of hemoglobin synthesis with a significant worldwide burden, which result in a wide spectrum of disease from the most severe transfusion-dependent form to the mildest asymptomatic carrier state. In this article, we discuss the importance of carrier, prenatal, and newborn screening for thalassemia. We examine the rationale for who should be screened and when, as well as the current methodology for screening. Deficiencies in the newborn screening program are highlighted as well. With the advent of inexpensive and rapid genetic testing, this may be the most practical method of screening in the future, and we review the implications of population-based implementation of this strategy. Finally, a case-based overview of the approach for individuals with the trait as well as prospective parents who have a potential fetal risk of the disease is outlined.