Beta-Globin Haplotypes and Alpha-Thalassemia 3.7 kb Deletion in Sickle Cell Disease Patients From the Occidental Brazilian Amazon

Abstract

Background: Sickle cell disease (SCD) includes a group of inherited red blood cell disorders. SCD patients vary widely from person to person. We describe beta^S and beta^C haplotypes and alpha-thalassemia 3.7 kb genotypes from SCD patients Fundacao Hospitalar de Hematologia e Hemoterapia do Amazonas, Manaus, AM.

Methods: Our survey included 139 HbSS and 11 HbSC patients. Molecular genotypes have been identified by PCR-RFLP and alpha-thalassemia 3.7 kb deletion by ASO-PCR. Male/female distribution was 42.3%/57.7%.

Results: The average age at enrolment was 19.1 years for HbSS and 25.85 years for HbSC. Average fetal hemoglobin was 11.27% for HbSS and 7.86% for HbSC. Anemia in HbSS patients was more severe and hemolysis twice as stronger as HbSC individuals. The frequency distribution of the most common beta-globin haplotypes among HbSS patients was 52.5% CAR/CAR, 23.7% CAR/Ben and 18% Ben/Ben. For the HbSC group, the haplotype distribution was 36.3% CAR/CI, 27.3% Benin/CI, 18.2% CAR/CII, 9.1% CAR/CIII and 9.1% Benin/CII. Of the HbSS patients, 13.7% and 2.8% were heterozygous and homozygous for the α-thalassemia 3.7 kb deletion, respectively. No HbSC patients presented the deletion.

Conclusions: Here we present the distribution of haplotypes beta^S and beta^C and alpha-thalassemia deletion 3.7 kb in a population sample with SCD from the Occidental Brazilian Amazon. Results have been analyzed in the context of hematological and biochemical profiles.




J Hematol. 2016;5(4):123-128
doi: https://doi.org/10.14740/jh310w