Effect of α-thalassemia and β-globin gene cluster haplotypes on the hematological and clinical features of sickle-cell anemia in Brazil

Abstract

To compare the features of sickle-cell anemia in Brazil with those in other locales, we studied the effects of the β-globin-like gene cluster haplotype and α-thalassemia upon the clinical and hematological features in 85 patients, The distribution of haplotypes differed from that in the United States and Jamaica, The Central African Republic (CAR) haplotype predominated; 34% of patients were CAR haplotype homozygotes, 45% CAR/ Benin homozygotes, and 11% Benin homozygotes. No Senegal haplotype chromosomes were observed, α-thalassemia was present in 17.5% of patients, HbF levels were higher in Benin homozygotes, compared with the other two groups (P < 0.05). Nearly half the patients with a CAR haplotype had leg ulcers, compared to 12.5% of the Benin homozygote group; stroke did not occur in α-thalassemia carriers, but neither result was statistically Significant, As in other studies, our results indicate that the CAR haplotype may be associated with more severe disease.