The volcano plot is a special 2-D scatter plot used to visualize significance and the magnitude of changes in features (e.g. genes or transcripts) within a given comparison. By convention, the X-axis represents the fold change between the two groups and is on a log2 log₂ scale.  On the other hand, the Y-axis shows the p-values from the statistical test of the comparison and it is on a log10 log₁₀ scale.

As a prerequisite for invoking the volcano plot, you must run a Differential gene expression analysis. When setting-up the analysis, include all relevant contrasts you would like to view the volcano plots for.

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