Figure 2.

Criteria for gene regulation: reproducibility compared with fold-change cut-off. The histograms bin genes according to the fold change in their expression in response to IFN-γ, Mtb, or both. Suppression (fold change <1) is represented as the negative inverse. Genes with fold change >20 or <(−)20 are omitted. P values were determined separately for each gene based on replication of results for that gene in six independent experiments. The left column tallies genes whose expression changed with P ≤ 0.05. The right column tallies genes whose expression changed (or not) with P > 0.05. Bars are black or white according to the twofold cut-off criterion typically used to identify regulated genes in microarray experiments that have been performed once or twice, but calculated here for 6 experiments. Black bars indicate genes that would be miscounted by this fold-change cut-off.