Beta-thalassemia in Brazil

ABSTRACT

1. Clinical, hematological, genetic and peripheral blood globin synthesis studies were carried out on 17 symptomatic Brazilian thalassemics and ther parents who live in the northeast of Säo Paulo State. The group inclued 8 beta--thalassemia homozygotes, 7 carriers of at least one beta+ gene, one delta beta-/beta--thalassemia double heterozygote and one beta- homozygote also carrying the alfa-chain variant Hb Hasharon (alfa2 47 His beta2). 2. The mean non-alfa/alfa ratio for globin biosynthesis of the patients lacking HbA (beta- homozygotes and delta beta-/beta- double heterozygotes) was 0.26 ñ 0.11 ( mean ñSD), which is not statistically different from the value of 0.32 ñ 0.06 obtained for the carriers of at least one beta+ gene. In contrast, the mean non-alfa/alfa ratio for the thalassemia major patients (0.22 ñ 0.07) was significantly lower than that obtained for the milder cases (0.34 ñ 0.06) although the beta/alfa ratios for the parents of the two groups were similar. 3. The heterogeneity within this group of Brasilian patients having two thalassemic genes, i.e. 60% who are beta- homozygotes and 40% who are carriers of at least one beta+ gene, is consistent with the Italian origin of most of these patients