DNA polymorphisms at BCL11A, HBS1L-MYB and Xmn1-HBG2 site loci associated with fetal hemoglobin levels in sickle cell anemia patients from Northern Brazil

Greice Lemos Cardoso, Isabela Guerreiro Diniz, Aylla Núbia Lima Martins da Silva, Daniele Almeida Cunha, Josivaldo Soares da Silva Junior, Camila Tavares Carvalho Uchôa, Sidney Emanuel Batista dos Santos, Saide Maria Sarmento Trindade, Maria do Socorro de Oliveira Cardoso, João Farias Guerreiro
2014 Blood Cells, Molecules & Diseases  
Increased levels of fetal hemoglobin (HbF, α2γ2) may reduce sickle cell anemia severity due to its ability to inhibit HbS polymerization and also reduce the mean corpuscular HbS concentration. We have investigated the influence of three known major loci on the HbF trait (HBG2, rs748214; BCL11A, rs4671393; and HBS1L-MYB, rs28384513, rs489544 and rs9399137) and HbF levels in SCA patients from the State of Pará, Northern Brazil. Our results showed that high levels of HbF were primarily influenced
more » ... imarily influenced by alleles of BCL11A (rs4671393) and HMIP (rs4895441) loci, and to a lesser extent by rs748214 Gγ-globin (HBG2) gene promoter. The SNPs rs4671393 and rs4895441 explained 10% and 9.2%, respectively, of the variation in HbF levels, while 4.1% of trait variation was explained by rs748214. The results can be considered as in accordance with the pattern of ancestry displayed by the SCA patients: 39.6% European, 29.6% African and 30.8% Native American, and reinforce the suggestion that studies of association between genetic modifiers and clinical and laboratory manifestations in Brazil must be controlled by ancestry.
doi:10.1016/j.bcmd.2014.07.006 pmid:25084696 fatcat:kaaeqaz3mvezzlp4yg3teeumwe