along with information on the number of genes identified as significantly altered by aging (P,0.05 and FDR-adjusted P,0.05). (PDF) Table S2 Mouse Datasets (Affymetrix Mouse Genome 430 2.0 array). This table lists datasets used to evaluate the effects of aging on gene expression in skin and other mouse tissues. The table includes experimental details for each dataset along with information on the number of genes identified as significantly altered by aging (P,0.05 and FDR-adjusted P,0.05). (PDF) Table S3 Empirical estimates of nucleotide frequency background distributions (human hg19 and mouse mm9). Human and mouse genomes were searched to identify matches with respect to position weight matrices representing motifs associated with known mammalian transcription factors. This table lists the region-specific estimates of the nucleotide References 1. Farage MA, Miller KW, Elsner P, Maibach HI (2008) Intrinsic and extrinsic factors in skin ageing: a review. Int J Cosmet Sci 30: 87–95. 2. 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