Update on thalassemia.

Many advances in the understanding and management of the thalassemia syndromes have been made during the past several years. Our knowledge of normal globin gene function and of the consequences of specific mutations has been advanced by identification of the genetic defects causing thalassemia. Prenatal diagnosis is now possible with molecular biology technology. Standards have been established for transfusion, splenectomy, prevention of postsplenectomy infection, and effective iron chelation therapy. Bone marrow transplantation is now available for those with a compatible familial donor. Research efforts currently are directed toward safer blood products, oral iron chelators, and improved understanding of the developmental regulation of globin gene expression for effective gene transfer.