Comparison of the occurrence of transcription factor (TF) matrix sequences in the promoters of redox detoxification genes down-regulated in SHR-A3 with redox scavenging genes not down-regulated. Promoters were assessed to determine, for each gene whether a TF matrix occurred or not in the promoter. For HNF1, nearly twice as many down-regulated detoxification genes contained the HNF1 matrix. Since genes regulated by a TF frequently have multiple occurrences of the matrix corresponding to this TF in the promoter, we then compared the average number of occurrences of each matrix per promoter across the two groups of genes.