Aequatus: An open-source homology browser

Abstract Background:The phylogenetic information inferred from the study of homologous genes helps us to understand the evolution of gene families, the study of homology plays a vital role in finding ancestral gene duplication events as well as identifying regions those are under positive selection within species. Conservation of homologous loci results in syntenic blocks, and there are various tools available to visualise syntenic information between species. These tools provide an overview of syntenic regions as a whole, reaching down to the gene level, but none provide any information about structural changes within genes such as the conservation of ancestral exon boundaries amongst multiple genomes. Findings:We present Aequatus, a standalone web-based tool that provides an in-depth view of gene structure across gene families, with various options to render and filter visualisations. It relies on pre-calculated alignment and gene feature information held in an Ensembl database, typically generated through, but not limited to, the Ensembl Compara workflow. We also offer Aequatus.js, a reusable JavaScript module that fulfils the visualisation aspects of Aequatus. Availability:Aequatus is an open-source tool freely available to download under GPLv3 license at https://github.com/TGAC/Aequatus and a demo is available at http://aequatus.tgac.ac.uk Contact:Anil.thanki@tgac.ac.ukRobert.davey@tgac.ac.uk