has specified data input has specified data output has format specification is published by is executed in Microarray data Gene expression data data visualization R data frame maDB http://bioconductor.org/packages/2.4/bioc/html/maDB.html Nandini Badarinarayan maDB allows to create a simple microarray database to store microarray experiments and annotation data into it. Affymetrix GeneChip expression values as well as values from two color microarrays can be stored into the database. Whole experiments or subsets from a experiment (or also values for a subset of genes in a subset of microarrays) can be fetched back to R. Additionally maDB provides different utility functions for the microarray data analysis like functions to draw MA plots or volcano plots with the data points color coded according to the local point density or functions that allow a replicate handling of miroarrays. Graph plot BioConductor Software R software differential expression analysis Bioconductor