Genomic locations of P450 gene clusters from Cyp1 (cluster 1), Cyp2 (clusters 2–5), Cyp3 (cluster 6), and Cyp4 (clusters 7 and 8) gene families. The image was obtained with the Affymetrix Integrated Genome Browser. Genes above the chromatin coordinates are transcribed from the plus strand, and genes below are transcribed from the minus strand. *, pseudogene; #, gene annotated in the National Center for Biotechnology Information database but not in the Integrated Genome Browser. Arrows connect gene names to the loci. Dashed lines separate panels from each other. Chr, chromosome.