Sickle cell/β0-thalassemia associated with the 1393 bp deletion can be associated with a severe phenotype.

In patients who have inherited both the sickle cell gene and the β-thalassemia (β-thal) gene, the nature of the β-thal mutation will impact on the disease phenotype. The β-thal mutation caused by the 1393 bp deletion has previously been described as having a mild clinical phenotype when inherited with the sickle gene. We describe three members of a family with this deletion who present with a more severe phenotype. The severity cannot be explained by their Hb F levels, or the XmnI-HBG2 polymorphism. This deletion cannot be presumed to be associated with a mild disease phenotype and we recommend that patients with Hb S/β(0)-thal are screened for this deletion.