Background: We previously introduced a method based on post hoc pairwise comparisons to
analyze gene expression responses. This method utilized directed graphs to
represent gene response to all treatment pairs. It has been found useful in
identifying structure-activity relationships among drugs and differentiating
genes sharing similar functional pathways. Directed graphs are descriptive,
visually expressive and can benefit subsequent functional analysis. Results:
mDAG is a web-based software package based on this established method for the
analysis, visualization, and interpretation of patterns of responses in gene
expression data involving multiple treatments. Genes with the same directed
graph patterns hypothetically share similar biological function, which may be
further analyzed using external tools. To facilitate subsequent functional
analysis, several well-known tools have been incorporated into mDAG to help
users explore hypotheses about gene function and regulation. This tool is
useful for any studies that analyze comparatively response patterns in gene expression data with multiple treatments (chemicals, cell types, etc.). Availability:
The (server/personal/demo) software is freely available at http://cetus.cs. memphis.edu/mdag.
Cite this paper
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