Real time RT-PCR analysis of relative expression of hERG1 C-terminal isoforms in different human tissues. Quantitative expression of hERG1FL and hERG1USO transcripts in human tissues was analyzed by real time PCR. The levels of hERG1 transcripts are normalized to the level of the GAPDH. Data are shown as the mean ± S.E. from three independent experiments. A, expression level of hERG1FL and hERG1USO in different tissues. The hERG1USO/hERG1FL expression ratios for heart, brain, colon, lung, and pancreas were 2.08, 0.96, 1.68, 1.94, and 1.31, respectively. B, expression level of hERG1FL and hERG1USO in the hearts and brains from three individuals.