To determine the incidence of delta+27 thalassaemia in Northern Sardinia we examined blood samples from 750 Sardinian schoolboys by PCR-based molecular analysis.
The incidence of delta+27 mutation was 1.2% in this study, i.e. twice as high as previously described on the basis of phenotypical studies ; the frequency of the bêta-thalassaemia is 10.5% and their interaction has been calculated at 0.0003.
The majority of delta+27 carriers are characterized by a HbA2 level lower than 1.9% and the mean HbA2 level is significantly lower than in normal subjects.
All compound heterozygotes for delta+27 and bêta-thalassaemia show a silent bêta-thalassaemic phenotype related to normalization of their HbA2 levels.
This study suggests that delta+27 thalassaemia should be borne in mind in counselling at-risk couples in which one member has the typical high HbA2 bêta-thal trait while the other shows normal or borderline HbA2 level.
In these subjects, PCR-based ECO 0 109 I digestion of the delta globin gene allows rapid detection of the delta+27 mutation.
Mots-clés Pascal : Thalassémie, Chaîne peptidique delta, Mutation ponctuelle, Incidence, Epidémiologie, Etudiant, Sardaigne, Italie, Europe, Enfant, Homme, Adolescent, Hémopathie, Anémie hémolytique, Hémoglobinopathie, Maladie héréditaire, Thalassémie delta
Mots-clés Pascal anglais : Thalassemia, Delta-Peptide chain, Point mutation, Incidence, Epidemiology, Student, Sardinia, Italy, Europe, Child, Human, Adolescent, Hemopathy, Hemolytic anemia, Hemoglobinopathy, Genetic disease
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0177263
Code Inist : 002B19A01. Création : 21/05/1997.