This is an image of a microarray from a lab project in the spring 2010 Genomics class.  Each spot represents one of the ~6200 genes that are found in the budding yeast Sacchraomyces cerevisiae. In this case, gene expression at different temperatures is being compared by isolating mRNA from cells grown at each temperature, labeling each with a different colored fluorescent marker, and exposing both to the DNA present on the microarray.  While most of the genes show strong expression at 23 degrees C (green), a few show strong expression at 37 degrees C (red), the temperature in which mutations of interest in these strains are active.  The class is currently working to identify these spots and understand why these particular genes may show elevated expression at elevated temperatures with these mutations.