Fig. 2

Effect of selenium supplementation on the number of differentially expressed (P < 0.01) genes in four tissues of mice. When genes were changed by more than one treatment (shown in intersecting regions), the denominator indicates the total number of genes changed and the numerator indicates how many of those genes were changed in the same direction by all treatments. If a ratio is not shown for a given intersection, all genes were changed in the same direction by all treatments. As described in the “Materials and methods,” there were fewer genes represented on the array used for the intestine which explains, in part, the lower number of differentially expressed genes in this tissue; the percentage of differentially expressed genes (relative to the total number of genes represented on the array) for each tissue is stated in the “Results”