Molecular characterization of β‐thalassaemia in 174 Greek patients with thalassaemia major

Abstract
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.