RESUMO
We describe a new δ-globin variant, Hb A2-Tunis [δ46(CD5)Gly â Glu; HBD: c.140G>A]. This hemoglobin (Hb) variant displayed a faster electrophoretic mobility than normal Hb A2 and was expressed at 3.2%. The molecular defect was characterized by DNA sequencing analysis. Hb A2-Tunis was found in a carrier of a ß(0)-thalassemia (ß(0)-thal) [IVS I-1 (ß143, G>A); HBB: c.92 + 1G>A] and Hb C [ß6(A3)Glu â Lys; HBB: c.19G>A], presenting with a normal Hb A2 level. Phenotype and genotype investigations revealed that the patient has a total Hb A2 level of 7.1% that was expected for a ß-thalassemia (ß-thal) minor carrier.
Assuntos
Hemoglobina A2/genética , Hemoglobinas Anormais/genética , Mutação de Sentido Incorreto , Globinas delta/genética , Adulto , Idoso , Sequência de Bases , Análise Mutacional de DNA , Saúde da Família , Feminino , Genótipo , Ácido Glutâmico/genética , Glicina/genética , Hemoglobina C/genética , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Mutação Puntual , Tunísia , Globinas beta/genética , Talassemia beta/genéticaRESUMO
We describe a new delta-globin variant, Hb A2-Pasteur-Tunis [delta59(E3)Lys-->Asn, AAG-->AAC]. This hemoglobin (Hb) displayed an electrophoretic mobility faster than normal Hb A2 and was expressed at 2.2 %. The molecular defect was characterized by DNA sequencing and confirmed by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)-designed protocol. Hb A2-Pasteur-Tunis was found in a carrier of a codon 39 (C-->T) beta0-thalassemia (thal), presenting with a normal Hb A2 level. Phenotype and genotype investigations revealed that the total Hb A2 level of the patient was that expected for a minor beta-thal (4.8%).