The connectivity maps approach is a rank-based enrichment method utilizing the KS test (Lamb et al., 2006). It measures the similarities of expression signatures based on the enrichment of up- and down-regulated genes at the top and bottom of sorted (ranked) gene lists.

## Query drug signatures

The following uses the 1,497 age-related gene expression signatures from Peters et al. (2015) as a query against the CMAP signatures. The results are sorted by the ES Distance and the top scoring 20 drugs are given below. The full result table is
written to a file named drugcmap2.xls.

## Query disease signatures

The same query is performed against a reference set of disease expression signatures. The results are sorted by the ES Distance and the top scoring 20 drugs are given below. The full result table is written to a file named diseasecmap2.xls.