Figure 4
'Volcano plots' for CodeLink and GeneChip. Each point represents a gene from the uniquely common set of 10,763 genes between platforms. Data points highlighted in blue represent genes which are concordantly 'present' in both tissues. The log10 ratio of expression (brain/pancreas) is shown on the x-axis and the p-value, from a two-tailed Student's t-tests on normalized log-transformed intensities, is shown on the y-axis. The vertical dashed lines represent 2-fold change ratios and the horizontal dashed line represents the statistical-significance level where p = 0.01.