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IGB can create several useful graphs from annotation tracks. Although the Depth graph can be utilized for all annotations, the usefulness shines, in combination with the Mismatch graph, with .bam and other short read alignment files. Here, you can see how many reads are present at each nucleotide position (Depth) and where mismatches occur as compared to the genomic sequence file.
Graph tracks, such as these, can be saved in your choice of format: .bgr, .sgr, or .gr. Details about these formats can be found in File Formats.
Depth Graph
You can generate an overview of the relative density of annotation coverage across an entire chromosome. The Make Annotation Depth Graph feature dynamically graphs the number of annotations in a track that are present at each nucleotide across the genomic sequence. When you are completely zoomed in, and each pixel represents a single nucleotide base, the graph shows actual values for the number of reads aligned at that genomic location. Using the Select tool to hover over a particular point in the graph will open a tooltip with the actual number of reads at that point.
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