RESUMO
OBJECTIVE: To determine the characteristic features of the rare hemoglobin (Hb) variant Hb Yaizu to enable laboratory diagnosis of the hemoglobin variants during screening programs. MATERIALS AND METHODS: Genomic DNA was obtained from the 4 members of a family living in Denizli province, an Aegean region of Turkey. Blood cell counts, hemoglobin composition, hemoglobin electrophoresis (both alkaline and acid), HPLC analysis, DNA sequencing and beta globin gene cluster haplotypes were done. RESULTS: Hb Yaizu carriers were apparently healthy individuals. Hb Yaizu was slightly faster than Hb S at alkaline pH, but slower than Hb S at acidic pH in hemoglobin electrophoresis. An abnormal hemoglobin peak was observed with a retention time of 4.77 min in HPLC analysis attributed to Hb Yaizu. Two members of the family were heterozygous Hb Yaizu [beta 79(EF3) Asp>Asn] confirmed by DNA sequencing. The mutation was found to be linked with the Mediterranean haplotype I [+----++]. CONCLUSION: We have presented the details of Hb Yaizu, a rare hemoglobin variant that may be important to hemoglobinopathy screening programs, although its clinical significance is unclear.
Assuntos
Variação Genética/genética , Hemoglobinas Anormais/genética , Sequência de Bases , Contagem de Células Sanguíneas , Cromatografia Líquida de Alta Pressão , Eletroforese , Feminino , Humanos , Recém-Nascido , Família Multigênica , Mutação , Triagem Neonatal , Linhagem , Projetos PilotoRESUMO
Hb Beograd [beta121(GH4)Glu-->Val, GAA-->GTA] is a rare variant first reported in Yugoslavia and then in Turkey, Australia and New Zealand. We report two further unrelated cases from Turkey. The importance of identifying Hb Beograd at the molecular level, especially in regions where Hb D-Los Angeles [beta121(GH4)Glu-->Gln, GAA-->CAA] is prevalent, is emphasized.
Assuntos
Substituição de Aminoácidos/genética , Hemoglobinas Anormais/genética , Mutação Puntual , Talassemia beta/genética , Feminino , Hemoglobinas Anormais/química , Humanos , Masculino , Turquia , Talassemia beta/etnologiaRESUMO
Since the first observation of hemoglobin S (Hb S) in Turkey by Aksoy, the number of hemoglobin variants reported was increased. Beta globin gene cluster haplotypes are being used to determine the origin of the mutations under interest. We studied the beta globin gene cluster haplotypes for the six different abnormal hemoglobins which are Hb S, Hb D-Los Angeles, Hb G-Coushatta, Hb E, Hb E-Saskatoon and Hb J-Iran observed in Turkey. In this study, we report two novel haplotypes [- + + - - - +] and [- + - + + +] in association with the Hb G-Coushatta mutation. The haplotype for the Hb J-Iran is also reported as [- + - + + + +] for the first time in world populations from Turkey.
