Assuntos
Hemoglobina Falciforme/genética , Hemoglobinas Anormais/genética , Deleção de Sequência/genética , Talassemia alfa/genética , Adulto , Substituição de Aminoácidos , Camarões , Análise Mutacional de DNA , Feminino , Globinas/análise , Globinas/genética , Heterozigoto , Humanos , Focalização Isoelétrica , Mutação , Mapeamento de Peptídeos , Gravidez , Complicações Hematológicas na Gravidez/diagnósticoRESUMO
The relative proportions of the two gamma chain species (G gamma and A gamma) have been reinvestigated in newborns, during the physiological switch from foetal to adult haemoglobin, and in adults with some persistent expression of HbF. In newborns, with about 80% HbF, the G gamma percentage was close to 70% while in adult RBC, with less than 0.5% HbF, the G gamma chain was almost non-detectable and may reflect the completion of the foetal to adult switch. Conversely, in adult patients with HbF above 0.6%, usually accompanying some degree of marrow stimulation, the relative ratio of G gamma varied between 40 and 60%, independently of HbF level. This ratio corresponds to what has been described in the literature as being the adult type of HbF. In all the cases where we found higher levels of G gamma, the results could be explained by the presence of a specific genetic background such as the Senegalese haplotype in sickle cell disease.