tabix – Generic indexer for TAB-delimited genome position files Tabix indexes a TAB-delimited genome position file in.tab.bgz and creates an index file ( in.tab.bgz.tbi or in.tab.bgz.csi ) when region is absent from the command-line. The input data file must be position sorted and compressed by bgzip which has a gzip(1) like interface. After indexing, tabix is able to quickly retrieve data lines overlapping regions specified in the format "chr:beginPos-endPos". (Coordinates specified in this region format are 1-based and inclusive.) Fast data retrieval also works over network if URI is given as a file name and in this case the index file will be downloaded if it is not present locally.