Distribution of ranks according to the three methods of array pre-processing (PDNN, RMA and MBEI). Significance of inter-strain differences is presented as a plot of logarithm of q-value versus expression level. Particular ranks are marked with colour as indicated on the left. Significance steps for ranks are marked with green horizontal lines. 1528 significant probe-sets are presented below as dots marked with light blue. Additionally, selected for qPCR genes were marked with yellow triangles with gene symbols (Atp1a2 – 1455136_at, Comt – 1418701_at, Gabra1 – 1436889_a, Gabra2 – 1455444_a, Grm7 – 1459532_at, Kcnj9 – 1450712_at, Syt4 – 1415844_at, Gfap – 1440142_s_at, Mtap2 – 1440699_at, Hprt1 – 1448736_a_at).