Figure 3.

Distributions of correlations for the Illumina HumanRef-8 BeadArrays (A) and the Affymetrix HG-U133 Plus 2 arrays (B). Correlations near −1 and 1 reflect probes whose targets are differentially expressed between the two samples. Correlations near zero reflect probes which do not show a dilution effect. The dilution effect is more pronounced for probes targeted at ‘known’ genes. This effect is stronger for Illumina (C) than for Affymetrix (D), though the Illumina platform has fewer probes which cannot be assigned to known genes (Table 1). For complete data see the Supplementary Data.