Probe signal detection. Detection coverage plots for both patients showing overlap in probe detection between dilutions. The two panels correspond to the two patients used for the dilution assessment. The horizontal axis corresponds to dilution, or amount of input RNA. For the vertical axis, the average intensity across the six dilutions was calculated for each patient separately. These average values were then ranked in abundance from 1 (lowest average abundance) to 735 (highest average abundance). The vertical axis corresponds to this ranking. The left column for each dilution corresponds to probes detected; and a black horizontal line is drawn only if a probe is detected in that dilution; white space if a probe is not detected. Due to the density of the probes in the column, a second column is included for each dilution indicating negative detection calls; a gray horizontal line is drawn if the probe is not detected; white space if a probe is detected. Thus, a probe detected (or not detected) in all dilutions would have a black (or gray) line in all dilutions.