Dosage compensation and expression level. (a-d) Ratio intensity (MA) scatterplots showing two-dose array expression values plotted against fold difference in expression in one-dose versus two-dose. (a,b) The full 21-line data set from microarray experiments. Expected values for full compensation (thin solid lines) and non-compensation (thin dashed lines) are shown. (c,d) Data from three lines tested by Illumina RNA-Seq (yellow), SOLiD RNA-Seq (green) or Nimblegen array (black). Trend-lines for each plot are shown (bold lines). (e) Measurements on External RNA Control Consortium (ERCC) control RNAs of known relative abundance (for example, spike-ins) with 1:1 and 1.5:1 ratios across the two mixtures (mix 1 and mix 2). (c,d,e) Expected values for 1:1 (solid line) and the two 1:1.5 ratios (dotted lines) are shown.