Dear BioC, I am working on ChIP-chip / ChIP-Seq data and I would like to do average gene mapping using absolute instead of relative coordinates. Does anyone have some idea or knows a package to do this ? In more details, I want to do a plot of different histone modification enrichments (from WIG files) on a composite average gene using absolute coordinates like in PMID 17679090. In general people are using relative gene mapping (as first proposed by the Young lab in 2005 PMID 16122420) but this technique (easy to implement since each coding region is simply divided into equally sized bins) often introduce a bias for histone marks/proteins which localized at an absolute distance from the start (or the end) of a gene (and the bias is even worst when people group genes by their length). Thanks Arnaud.