RESUMO
A man who did not produce and beta-chains did not suffer from a severe beta-thalassaemia. He was heterozygous for Hb G Philadelphia. It has been suggested that this haemoglobin variant was associated with alpha-thalassaemia and that interaction between alpha-thalassaemia and beta-thalassaemia decreased the imbalance of alpha/beta-globin biosynthesis and thereby the severity of the beta-thalassaemic disorder. Association of Hb G Philadelphia and alpha-thalassaemia in this man and his family is now demonstrated using bone marrow and reticulocytes of the propositus and one of his sons and reticulocytes only of another son.
Assuntos
Globinas/biossíntese , Hemoglobinas Anormais/isolamento & purificação , Talassemia/sangue , Medula Óssea/metabolismo , Células da Medula Óssea , Feminino , Humanos , Masculino , Reticulócitos/metabolismo , Talassemia/genética , Talassemia/metabolismoAssuntos
Globinas/genética , Hemoglobinas Anormais/genética , Talassemia/genética , Adulto , Pré-Escolar , Feminino , Heterozigoto , Homozigoto , Humanos , Masculino , Oxigênio/sangue , Linhagem , Talassemia/sangueRESUMO
The question, "Is Hb G alpha Philadelphia linked to alpha-thalassaemia?" was first posed because the abnormal haemoglobin is found in heterozygotes at a concentration greater than 25%, the proportion predicted from a 4 alpha-chain gene model. Globin chain biosynthesis was studied in a West Indian family in which one parent had beta + thalassaemia and the other was heterozygous for the G alpha Philadelphia chain gene. The former had a globin chain production ratio alpha/beta well above 1, while the latter had a ratio significantly less than 1. One child of the marriage had inherited the beta + thalassaemia from one parent and the G alpha Philadelphia chain gene from the other and showed the typical picture of alpha/beta-thalassaemia (alpha/beta ratio slightly above normal). It is explained in the discussion that the evidence favours a close linkage of 2 alpha-chain genes.
Assuntos
Ligação Genética , Hemoglobinas Anormais/biossíntese , Talassemia/genética , População Negra , Feminino , Frequência do Gene , Genes , Genótipo , Globinas/biossíntese , Heterozigoto , Humanos , Masculino , Linhagem , FenótipoRESUMO
A homozygote for the gene controlling Hb D Punjab is described. The diagnosis is supported by the peptide analysis of the haemoglobin and the examination of both parents. There was no anaemia or reticulocytosis and there was balanced synthesis of both the alphaA- and betaD-globin chains in reticulocytes. However, the oxygen affinity of the haemolysate had a small but significantly higher oxygen affinity than normal. The only other abnormalities were a somewhat decreased osmotic fragility and a slight anisocytosis of the red cells.
Assuntos
Hemoglobinas Anormais/biossíntese , Homozigoto , Aminoácidos/análise , Bilirrubina/sangue , Eritrócitos/fisiologia , Globinas/biossíntese , Hemoglobinas Anormais/metabolismo , Humanos , Índia , Masculino , Fragilidade Osmótica , Oxigênio/metabolismo , LinhagemRESUMO
Gm and Inv polymorphism has been investigated on a sample of the general Greek population (N = 256) and on a sample of the Achaia population of Northwestern Peloponnusus (N = 150). The estimated frequencies were, respectively in the two groups: Gm1, 0.156 vs. 0.180; Gm1,2,0.010 vs. 0.017; Gm4,12, 0.834 vs. 0.803; Inv (+1), 0.125 vs. 0.140.
