RNA detection limits. (A) Total RNA versus 5 μg amplified RNA yielded a coefficient of 0.789 after two rounds of amplification (n = 6,096 genes) (B) The correlation for all genes between total RNA and a serially diluted 0.5 μg aliquot that was removed from the 5 μg sample and amplified 2 rounds yielded a coefficient of 0.7 (n = 6,102 genes). (C) The correlation between gene expression ratios for all genes between total RNA and a 0.05 μg aliquot that has been serially diluted from the 0.5 μg aliquot yielded a coefficient of 0.669 (n = 6,114 genes). (D-F) Venn diagrams depicting outlier concordance between the samples featured in (A-C, respectively). Extraction methods for all genes and outliers are found in the methods.