Molecular basis of beta-thalassemia intermedia in a southern Italian region (Puglia).
We investigated the molecular bases for a mild phenotype by alpha-, beta- and gamma-globin gene analyses in 22 patients with transfusion-independent thalassemia intermedia (15) or a late-presenting form of thalassemia major (7) originating from Puglia, a region of southern Italy. Twenty-two patients with thalassemia major served as controls. The beta+ IVS-I nt 6 of the beta-globin gene and the C----T substitution at position -158 5' of the G gamma-globin gene were detected more frequently in patients with thalassemia intermedia or late-presenting thalassemia major considered together as compared to those affected by typical transfusion-dependent thalassemia major. Three of 15 patients with thalassemia intermedia had the triple alpha-globin gene arrangement in the heterozygous (2) or homozygous state (1) in association with heterozygous beta zero-thalassemia. From these results, we may conclude that the inheritance of a mild beta-thalassemia allele such as the beta+ IVS-I nt 6 mutation, in the homozygous or heterozygous state, the coinheritance with homozygous beta zero-thalassemia of the -158 (C----T) G gamma gene promoter mutation and the presence of heterozygous beta-thalassemia/triple alpha-globin gene arrangement are the most common reasons accounting for the development of attenuated forms of beta-thalassemia in Puglia.
Leoni
G B
GB
Istituto di Clinica e Biologia dell'Età Evolutiva, Università degli Studi di Cagliari, Italia.
Rosatelli
C
C
Vitucci
A
A
Addis
M
M
Loi
A
A
Tannoia
N
N
Cao
A
A
D000510:Alpha-Globulins / Q000235:genetics; D001609:Beta-Globulins / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D015321:Gene Rearrangement / Q000235:genetics; D006239:Haplotypes; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007558:Italy; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D013789:Thalassemia / Q000097:blood / Q000235:genetics*; D005719:gamma-Globulins / Q000235:genetics
D000510:Alpha-Globulins; D001609:Beta-Globulins; D005719:gamma-Globulins