Mecp2 transcripts are below the level of detection in Mecp2 /MeCP2-deficient astrocytes. Individual astrocyte samples are shown on the X axis. The Y axis shows the relative microarray signal intensity. In the Affymetrix Mouse 430 2.0 array, Mecp2 is represented by two probe sets, 1460246_at and 1438930_s_at. Both probe sets produced consistent hybridization signals. MeCP2, methyl-CpG-binding protein 2.