Allelic expression imbalance analysis of Cx40- A mRNA. Shown are eight atrial tissue samples heterozygous for the GJA5 3′ UTR insertion/deletion polymorphism and the indicator SNP rs1043806. Each bar represents the allelic expression ratio for an individual subject, based on peak heights for cDNA/gDNA at the indicator SNP site. Significant allelic mRNA imbalance is found when the cDNA allelic ratio falls outside of a 95% confidence interval created by the gDNA allelic ratios (dotted lines). The G allele of the indicator SNP was always found together with the deletion allele of the insertion/deletion polymorphism. Six samples demonstrated weak allelic expression imbalance of Cx40 favoring the deletion-G allele. One sample was not significantly associated with allelic expression imbalance and another sample exhibited Cx40 expression imbalance in the opposite direction.