Beta-thalassemia mutations in the Portuguese; high frequencies of two alleles in restricted populations.
We report the characterization of seven different beta-thalassemia mutations in 131 newly diagnosed Portuguese beta-thalassemia heterozygotes. Methodology included the detection of abnormal fragments by agar gel electrophoresis of PCR-amplified DNA fragments after digestion with specific restriction endonucleases, as well as hybridization with synthetic nucleotide probes and sequencing of amplified DNA. Four mutations, including the newly discovered TGG-->TGA change at codon 15, occurred in excess of 10% and accounted for some 90% of the beta-thalassemia alleles in this population. The geographical distribution is uneven; the TGG-->TGA mutation at codon 15 was primarily observed in the coastal region north of Lisbon, while the IVS-I-6 (T-->C) mutation was confined to the central part of the country.
Tamagnini
G P
GP
Department of Hematology, Centro Hospitala de Coimbra, Portugal.
Gonçalves
P
P
Ribeiro
M L
ML
Kaeda
J
J
Kutlar
F
F
Baysal
E
E
Huisman
T H
TH
D000483:Alleles; D001483:Base Sequence; D003062:Codon; D004252:DNA Mutational Analysis; D005260:Female; D005914:Globins / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D016133:Polymerase Chain Reaction; D011174:Portugal / Q000453:epidemiology; D017086:beta-Thalassemia / Q000453:epidemiology / Q000208:ethnology / Q000235:genetics*
D003062:Codon; D005914:Globins