RESUMO
We report in this paper a novel thalassemia mutation (insertion of a single A nucleotide within the exon 1, at codon 18, of the beta-globin gene) associated with a deletion of the deltabeta-globin gene region, in a patient exhibiting high persistence of fetal hemoglobin. The novel mutation causes a frameshift with the generation of a UGA stop codon. Analysis of the parent's DNA demonstrates that the A insertion and frameshift mutation are inherited from the father, while the deltabeta-globin gene deletion is inherited from the mother. Gene dosage analysis and deletion-specific PCR demonstrate that the deletion is the (deltabeta)(0) Sicilian deletion, involving a 13.4-kb deltabeta-globin gene region.
Assuntos
Códon , Hemoglobina Fetal/genética , Mutação da Fase de Leitura , Globinas/genética , Talassemia/genética , Células Cultivadas , Criança , Cromatografia Líquida de Alta Pressão , DNA/genética , Éxons , Feminino , Deleção de Genes , Dosagem de Genes , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Fenótipo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNARESUMO
Results from a collaborative exercise with proficiency testing conducted by 20 Italian laboratories on the 15 loci included in the Identifiler kit were analyzed by allele sharing methods and by standard population genetics tests. The validated database, including about 1500 subjects, was merged with that of a previous exercise conducted on nine loci, and the resulting allele frequencies, subdivided by Italian region, were published on-line.