Figure 1.

Visualization of Microarray data. A) R-I plot, in which the log₂ of the ratio of mean intensities in CF-vs.-non CF samples is plotted against the log of their product, demonstrating the absence of an intensity dependent fold-change bias. The regulated genes chosen for further analysis using the RP statistic (p < 0.0001 cut-off) are shown in red (up-regulated genes) and green (down-regulated genes). B) Dendrogram of clustered samples, in which CF and non CF samples cluster with respect to their phenotype. C) Volcano plot of microarray data, in which the Log₂ of the RP statistic is plotted against Log₂ of Fold Change. The p < 0.0001 cut-off (horizontal dotted line) illustrates the gene list chosen for further analysis. Genes outside the vertical dotted lines have more than 2-fold differential expression.