Figure 1

MA plots of trisomic and disomic microarray probe-sets from 3 different brain regions (cerebral cortex, cerebellum and hippocampus) at 4 postnatal (P) time points (P1, P15, P30 and P84). The Y-axis represents the M value, which is the ratio (log₂(T/D)) whereas the X-axis represents the A value, which is the mean ratio (1/2xlog₂(TxD)). T and D represent the intensities of microarray probe-sets for Ts1Cje and disomic samples, respectively. Each blue dot represents a single probe. Red dotted lines denote the cutoff at M values of 0.58, signifying 1.5-fold upregulation of microarray probe-sets.