Allelic expression of ERβ 3'UTR SNPs in breast tumor samples. A. Genomic DNA was sequenced in two independent assays. cDNA synthesis was performed twice and each cDNA was sequenced in two independent assays. For each sample and allele, the average peak heights from the four cDNA sequencing assays were normalized by the average peak heights from the two DNA sequencing assays. The results from five breast tumor samples heterozygous for each SNP are presented as relative allelic ratios for cDNA versus genomic DNA. Data are shown as mean ± SD, with allele G set to 100%. (a) ERβ1 3'UTR polymorphism (rs4986938 G↔A); (b) ERβ2 polymorphism (rs928554 G↔A).B. Representative examples of genomic DNA and mRNA sequencing. (a) ERβ1 3'UTR polymorphism (rs4986938); (b) ERβ2 3'UTR polymorphism (rs928554). Observe that for rs928554 G↔A, the bottom strand was sequenced therefore the DNA sequence reads C and T, respectively.