First description of a frameshift mutation in the alpha1-globin gene associated with alpha-thalassaemia.
A frameshift mutation in the alpha1-globin gene, responsible for a clinically mild alpha-thalassaemia phenotype, has been characterized in a Spanish woman. After excluding the most common forms of alpha-thalassaemia found in the Mediterranean area, both alpha-globin genes (alpha1 and alpha2) were amplified and analysed selectively by non-radioactive single-strand conformation polymorphism (SSCP). An abnormal SSCP mobility was present in the second exon of the alpha1-globin gene and direct sequence analysis revealed a 13 bp deletion (between codons 51 and 55) affecting a single allele. The consequence of this mutation is a reading frameshift leading to a novel amino acid coding sequence from codons 51-61 and a premature stop signal at new position 62, which results in a net reduction of the affected alpha-globin chain output. The presence of this new mutation was confirmed by restriction enzyme analysis of the specific PCR product.
Ayala
S
S
Haematology Laboratory Department, Hospital Clínic i Provincial, University of Barcelona, Spain.
Colomer
D
D
Aymerich
M
M
Abella
E
E
Vives Corrons
J L
JL
D000368:Aged; D004591:Electrophoresis, Polyacrylamide Gel; D005091:Exons / Q000235:genetics; D005260:Female; D016368:Frameshift Mutation; D005914:Globins / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D010375:Pedigree; D016133:Polymerase Chain Reaction; D017421:Sequence Analysis; D017085:alpha-Thalassemia / Q000235:genetics*
D005914:Globins