SEVERITY OF BETA-THALASSEMIA DUE TO GENOTYPES INVOLVING THE IVS-I-6 (T-]C) MUTATION

Among individuals of Mediterranean or Middle Eastern descent, the IVS- I-6(T-->C) mutation is one of the most common causes of beta-thalassem ia. In this report, we describe the clinical phenotypes of a group of beta-thalassemia patients who are compound heterozygotes for the relat ively mild 1VS-I-6(T-->C) beta-thalassemia mutation and more severe be ta(+)- or beta degrees-thalassemia mutations. Although most of these p atients are transfusion-dependent, the requirement for regular transfu sions generally occurred late in childhood, A correlation between conc omitant alpha-thalassemia and a mild transfusion-independent phenotype is not apparent, indicating the involvement of other ameliorating det erminants. (C) 1995 Wiley-Liss, Inc.