Coexistence of hereditary spherocytosis (HS) due to band 3 deficiency and beta-thalassaemia trait: partial correction of HS phenotype.
A kindred with hereditary spherocytosis and beta-thalassaemia trait was identified. Detailed studies of the red cell membrane proteins on polyacrylamide gels with sodium dodecyl sulphate (SDS-PAGE) demonstrated the presence of band 3 (anion transporter) deficiency in all HS subjects (20-25% reduction) whereas spectrin content was in the normal range. The molecular defect of beta thalassaemia in this kindred was due to a beta(0) codon 39 (C-T) mutation, as assessed by beta globin gene amplification and ASO-probe hybridization. Seven subjects of this family were studied: two were normal, two had HS alone, two co-inherited HS and beta-thalassaemia trait, and one had beta-thalassaemia trait only. The two subjects with HS alone had a typical clinical form of spherocytosis with anaemia, reticulocytosis and increased red cell osmotic fragility. The two with both HS and beta-thalassaemia trait were not anaemic and showed a small, well-compensated haemolysis. Hence the finding of red cells with abnormalities of both HS and beta-thalassaemia indicates that beta-thalassaemic trait 'silences' HS caused by band 3 deficiency.
Miraglia del Giudice
E
E
Paediatric Department, University of Naples, Italy.
Perrotta
S
S
Nobili
B
B
Pinto
L
L
Cutillo
L
L
Iolascon
A
A
D000328:Adult; D001457:Anion Exchange Protein 1, Erythrocyte / Q000172:deficiency*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D010641:Phenotype; D013103:Spherocytosis, Hereditary / Q000097:blood / Q000150:complications* / Q000235:genetics; D017086:beta-Thalassemia / Q000097:blood / Q000150:complications* / Q000235:genetics
D001457:Anion Exchange Protein 1, Erythrocyte