Comparability and concordance of replicated microarray data

To measures the comparability and concordance of Illumina microarray, a series of 30 samples of Universal Human Reference RNA (UHRR) were set as controls for every single chip of total 30 Human-Ref V2 BeadChips. The average bead number of the 30 arrays was 42.3±8.1 for any bead type over the 22,184 probes. A high average correlation coefficient (r) value was obtained as 0.9908±0077 relative to each other of the expression intensity values from the 30 duplicate UHRR samples. 30 UHRR (Stratagene; La Jolla, CA) samples were used as controls for each of 30 BeadChips.