RT-qPCR analysis of CYP expression for 12 genes. CYP1A, 1B, 1C1, 1D1, 2K16, 2P6, 2U1, 2V1, 2AA4, 2AA6, 2AA11 and CYP20A1 were examined. qPCR confirms the microarray results for 10 of the 12 CYP genes examined. Both microarray and qPCR analyses were normalized by ARNT2 expression. Only CYP1D1 and CYP2AA4 exhibit deviations from linearity.