Resources : HeatmapGenerator

Heatmaps History

Heatmaps are two-dimensional graphical false-color image representations of data using a user-defined color scheme to display values in a data matrix. In the medical research community, heatmaps are used to comparatively illustrate gene expression levels across a number of different samples (e.g., cells under different experimental conditions or samples from different patients) obtained from DNA microarray studies or high-throughput sequencing methods such as RNAseq. Genes that are upregulated (high relative expression value) are colored differently than genes that are downregulated (low relative expression value), thus providing a simultaneous visual representation of gene expression levels across multiple different samples. Heatmaps can be used to, for example, understand what groups of genes are turned on or turned off in various cancer samples as compared to control samples. For instance, heatmaps have been used for gene expression profiling of breast cancer samples to study the differential patterns of gene expression across multiple individual tumors.