A NOVEL MEDITERRANEAN DELTA-BETA-THALASSEMIA DETERMINANT CONTAINING THE DELTA+27 AND BETA-DEGREES-39 POINT MUTATIONS IN CIS

The term deltabeta-thalassemia with normal HbF has been recently proposed to define heterogenous delta and beta globin gene molecular defects involving the same chromosome in cis. Here, we describe a Sardinian family in which three members showing microcytosis, border-line HbA2 levels and normal HbF proved to be heterozygotes for delta+27 and beta-degrees-39 point mutations in cis by allele specific oligonucleotyde hybridization as well as by ECO 0 109 I endonuclease digestion and electrophoresis. As some of these beta-thalassemia carriers shows normal HbA2 levels, knowledge of the molecular basis of this novel deltabeta-thalassemia silent phenotype would be useful in thalassemia screening and genetic counselling. (C) 1994 Wiley-Liss, Inc.