MOLECULAR CHARACTERIZATION OF BETA-THALASSEMIA IN 174 GREEK PATIENTS WITH THALASSEMIA MAJOR

The mutations producing β‐thalassaemia in 174 Greek patients with thalassaemia major were investigated by dot‐blot hybridization of oligonucleotide probes to genomic DNA amplified by the polymerase chain reaction procedure, by direct sequencing of amplified DNA, and by gene mapping. β‐thalassaemia in Greeks was found to be very heterogeneous at the molecular level as 17 different mutations were observed; 86.6% of the β‐thalassaemic genes, however, could be identified with five probes: IVS‐I‐110 (G→A) (42.5%), codon 39 (C→T) (17%), IVS‐I‐1 (G→A) (13.2%), IVS‐I‐6 (T°C) (7.2%) and IVS‐II‐745 (C→G) (6→9%). Several mutations which had not previously been reported in the Greek population and which occurred at an incidence of 2% or lower were observed in this study. The information obtained will facilitate the prenatal diagnosis of β‐thalassaemia in Greece. Copyright © 1990, Wiley Blackwell. All rights reserved