transient expression assay of aγ-588 (a/g) mutations in the k562 cell line

background: in the previous study, we have shown that the presence of a allele at position -588 in aγ-globin gene was highly frequent and closely associated with fetal hemoglobin elevation among β-thalassemia intermedia patients. therefore, we decided to investigate whether this allele (a allele at -588) could result in an increase in aγ-globin gene expression to ameliorate the severity of the disease in thalassemia patients. methods: three constructs containing µ locus control region, aγ-globin and β-globin genes were designed and employed in the transient expression assay. the difference among constructs was in the promoter region of aγ-globin gene (a and g alleles at -588). a construct with t to c base substitution at -175 of aγ-globin, created by site-directed mutagenesis, was selected as positive control. the k562 cell line was transfected with the above constructs. subsequently, the expression of aγ-globin gene was determined by quantitative real-time reverse transcription-pcr. results: there was not a significant increase in the expression of aγ-globin gene in the construct containing a allele comparing the one with g allele at -588. conclusions: -588 (a>g) mutation does not play a major role in regulation of aγ-globin gene, suggesting that other factors may be involved.