Expression levels were measured for each of 12,000 genes on the Affymetrix U95Av2 GeneChip. Expression levels are shown for 5800 genes that were detected in the biopsies used in this study. A. Scatter diagrams comparing the RNA expression profiles obtained from two control women (r2 = 0.94). B. Scatter diagram showing mean RNA expression profiles for asthmatic and control subjects (r2 = 0.80). The mean expression levels for NOS2A and CX3CR1, two genes that are differentially expressed between the two groups, are indicated (see also Table 1 [see Additional file 1]). C to F. Scatter diagrams comparing the RNA expression profile obtained from a normal female to expression profiles obtained from each female asthmatic subject.