Hi Jaehoon, thanks for your feedback. You can overlay data from different samples in a DataTrack, however you are quite tightly limited by the fact that all the samples within one DataTrack will have to share the same coordinates. Obviously, this is a problem in many settings, for instance when reading data off different bigwig files. It has been on my to do list for quite some time now to provide support for more generic types of overlays through a dedicated OverlayTrack class, which should act as a sort of container for several other tracks. This should become available in the devel branch of the package in the next couple of weeks. I will keep you posted. Florian From: Jaehoon Shin <rookysh@gmail.com<mailto:rookysh@gmail.com>> Date: Friday, October 4, 2013 7:17 PM To: Florian Hahne <florian.hahne@novartis.com<mailto:florian.hahne@novartis.com>> Subject: overlay in GVIZ Dear Florian, First of all, thank you so much for a great software. I really enjoying using your software Gviz for my work. I have one question; I am wondering whether Gviz can allow users to overlay features as genome browser does. I would like to overlay two or more bigwig files with transparent colors in one track. If it does not have the feature, I am wondering whether you have a plan for incorporating it. Thanks! Jaehoon Shin Graduate student in Hongjun Song lab Johns Hopkins Medical Institutions Institute of Cell Engineering [[alternative HTML version deleted]]