In toxicological studies, DNA microarrays involve isolating mRNA from cells exposed to a toxicant and converting it into complementary DNA (cDNA). This cDNA is then fluorescently labeled and hybridized to the microarray. The intensity of fluorescence on each spot indicates the level of gene expression. By comparing the gene expression profiles of exposed and unexposed cells, researchers can identify which genes are upregulated or downregulated in response to the toxicant.
