The fetal hemoglobin (HbF) levels and ß S -globin gene haplotypes of 125 sickle cell anemia patients from Brazil were investigated. We sequenced the Gγ-and Aγ-globin gene promoters and the DNase I-2 hypersensitive sites in the locus control regions (HS2-LCR) of patients with HbF level disparities as compared to their ß S haplotypes. Sixty-four (51.2%) patients had CAR/Ben genotype; 36 (28.8%) Ben/Ben; 18 (14.4%) CAR/CAR; 2 (1.6%) CAR/Atypical; 2 (1.6%) Ben/Cam; 1 (0.8%) CAR/Cam; 1 (0.8%)

more »

... b-Indian, and 1 (0.8%) Sen/Atypical. The HS2-LCR sequence analyses demonstrated a c.-10.677G>A change in patients with the Ben haplotype and high HbF levels. The Gγ gene promoter sequence analyses showed a c.-157T>C substitution shared by all patients, and a c.-222_-225del related to the Cam haplotype. These results identify new polymorphisms in the HS2-LCR and Gγ-globin gene promoter. Further studies are required to determine the correlation between HbF synthesis and the clinical profile of sickle cell anemia patients.