Haplotipos del gen de la globina beta en portadoresde hemoglobina S en Colombia

Introduction: The hemoglobin S(HbS) mutation is accompanied by other mutations in the region of chromosome 11 known as "beta globin cluster". The pattern of combination of these polymorphismsgiving rise to the haplotypes that co-inherit the HbS mutation, are called haplotypes β^s and are of great epidemiological and clinical significance.Objective:The frequencies of major haplotypes associated with S beta-globin gene was determined inColombian patients heterozygous for hemoglobin S. Materials and methods: As part of the national neonatal screening program at Clínica Colsanitas,located in major cities of Colombia, nearly 1,200 children from different areas of the country wereexamined for hemoglobinopathies. The sickle cell trait was identified as the most common. S betaglobingene haplotypes were determined by PCR and restriction enzymes in 33 children with AShemoglobin electrophoretic patterns (carrier state). In addition, electrophoretic patterns of hemoglobin,fetal hemoglobin levels and hematologic parameters of each individual were identified. Results: The most frequent haplotypes in Colombia were the Bantúhaplotype (36.4 %), followed bySenegal (30.3 %), Benin (21.2 %) and Cameroon (12.1 %) haplotypes. Hemoglobin electrophoresisconfirmed the AS phenotype in all patients, and fetal hemoglobin levels below 1%. Other hematologicalparameters were normal in all cases. Conclusion: The HbS haplotypes found more frequently in the sampl were of African origin, and theirdistribution varied according to the place of origin of the individual. The most frequent corresponded tothe Bantu haplotype.