Rs231841 In KCNQ1 With Positive Natural Selection Is Associated With Hemoglobin A₂ Levels

Obsject:Our aim was to screen out the positive natural loci influencing the expression levels of HbF from the public database.Then we performed the association analysis to discuss the effect of genetic variants under positive natural selection associated with HbF levels on HbA₂ levels in the?-thalassemia individuals.Methods:The positive natural loci influencing HbF levels from the public database HapMap and NCBI was screened out.We collected the samples with?-thalassemia from the departments of pediatrics and prenatal diagnosis of the First Affiliated Hospital of Guangxi Medical University,Nanning,Guangxi Province,People's Republic of China?PRC?from January 2014 to March 2016.The levels of Hb A₂ and Hb F were measured.Then,we extracted DNA and preformed genotyping.Hardy-Weinberg equilibrium of the variant was detected by Haploview v.4.2.All genetic association analysis of the positive selection variant with Hb F and HbA₂ levels were performed by PLINK program.Results:Bioinformatics analysis showed that the rs231841 in KCNQ1 with positive natural selection on chromosome 11p15 was associated with the Hb F levels.A total of 1030 individuals of?-thalassemia was entered into our study.Genotype of rs231841 were CC,CA and AA.The linear regression analysis showed that the loci was significantly associated with Hb A₂ levels,but not associated with HbF.The presence of C allele was associated with elevating HbA₂ levels.Conclusion:Our results suggest that the rs231841 in KCNQ1 with positive natural selection is associated with HbA₂ levels in?-thalassemia individuals.The indviduals with C allele is associated with elevating HbA₂ levels.The loci doesn't associate with Hb F levels.