Association between Variants at BCL11A Erythroid-Specific Enhancer and Fetal Hemoglobin Levels among Sickle Cell Disease Patients in Cameroon: Implications for Future Therapeutic Interventions

OMICS. 2015 Oct;19(10):627-31. doi: 10.1089/omi.2015.0124. Epub 2015 Sep 22.

Abstract

Variants in BCL11A were previously associated with fetal hemoglobin (HbF) levels among Cameroonian sickle cell disease (SCD) patients, however explaining only ∼2% of the variance. In the same patients, we have investigated the relationship between HbF and two SNPs in a BCL11A erythroid-specific enhancer (N=626). Minor allele frequencies in rs7606173 and rs1427407 were 0.42 and 0.24, respectively. Both variants were significantly associated with HbF levels (p=3.11e-08 and p=6.04e-06, respectively) and explained 8% and 6.2% variations, respectively. These data have confirmed a stronger effect on HbF of genomic variations at the BCL11A erythroid-specific enhancer among patients with SCD in Cameroon, the first report on a West African population. The relevance of these findings is of prime importance because the disruption of this enhancer would alter BCL11A expression in erythroid precursors and thus HbF expression, while sparing the induced functional challenges of any alterations on the expression of this transcription factor in non-erythroid lineages, thus providing an attractive approach for new treatment strategies of SCD.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Alleles
  • Anemia, Sickle Cell / genetics*
  • Anemia, Sickle Cell / pathology
  • Cameroon
  • Carrier Proteins / genetics*
  • Child
  • Child, Preschool
  • Female
  • Fetal Hemoglobin / genetics*
  • Gene Expression
  • Gene Frequency
  • Haplotypes
  • Humans
  • Male
  • Middle Aged
  • Nuclear Proteins / genetics*
  • Polymorphism, Single Nucleotide*
  • Repressor Proteins

Substances

  • BCL11A protein, human
  • Carrier Proteins
  • Nuclear Proteins
  • Repressor Proteins
  • Fetal Hemoglobin