DETECTION OF BETA-GLOBIN AND DELTA-GLOBIN GENE-MUTATIONS BY PCR AND DIRECT DNA SEQUENCING IN AN INDIVIDUAL WITH NORMAL HBA2 BETA-THALASSEMIA

Normal HbA2 beta-thalassemia in a Greek individual was shown to be due to co-inheritance of beta and delta-thalassemias. The genetic defects were characterized by enzymatic amplification of the beta and delta-globin genes and direct genomic sequencing. Two children with a typical high HbA2 beta-thalassemia trait had inherited the beta-thalassemia allele whilst a third child had low-normal HbA2 associated with delta+ thalassemia. Segregation patterns confirmed that the delta+/beta-degrees thalassemia defects were present in trans*.