β‐globin gene cluster haplotypes in sickle cell patients from Panamá

Abstract

To analyze the frequency of the haplotypes of β-globin gene cluster in randomly selected patients with sickle cell disease (SCD), attended in the Children's Hospital of Panama. Five polymorphic sites in the β-globin gene cluster were analyzed by polymerase chain reaction (PCR) followed by restriction digestion and agarose gel electrophoresis in a total of 100 patients, including 95 homozygous for HbS (sickle cell anemia) and 5 compound heterozygotes for HbS and HbC genes (HbSC disease). The Bantu haplotype was predominant with a frequency of 51%, followed by the Benin (30%), Senegal (8.5%), and Cameroon (4%); other haplotypes were also identified. Genotype was CAR/CAR in 39 patients, BEN/BEN in 22, SEN/SEN in 6, CAM/CAM in 4, ARB/ARB in 1, CAR/BEN in 15, CAR/SEN in 5, CAR/Hp5 in 3, CAR/Hp1 in 1, BEN/Hp11 in 1, Atp Hp1/Hp1 in 2, and Atp Hp5/Hp5 in 1 individual. Hemoglobin concentrations, hematocrit, and mean corpuscular hemoglobin concentration values did not differ among homozygous forms of haplotypes. The mean HbF in all patients was 15.39 ± 1.21, whereas SEN/SEN patients had higher HbF than BEN/BEN patients (24.26 ± 4.18 vs. 13.17 ± 2.39, respectively, P < 0.05). The percentage of reticulocytes was highest in BEN/BEN and CAR/CAR, and it was associated with worst prognosis. The results show the presence of common β(S) haplotypes in Panama; the prevalence of African origin, and the similarity in the Panamanian and Colombian distribution of haplotypes.