Detection of orthologous exons and isoforms using EGIO.

Abstract

Alternative splicing is an important mechanism to generate transcriptomic and phenotypic diversity. Existing methods have limited power to detect orthologous isoforms. We develop a new method, EGIO, to detect orthologous exons and orthologous isoforms from two species. EGIO uses unique exonic regions to construct exon groups, in which process dynamic programming strategy is used to do exon alignment. EGIO could cover all the coding exons within orthologous genes. A comparison between EGIO and ExTraMapper shows that EGIO could detect more orthologous isoforms with conserved sequence and exon structures. We apply EGIO to compare human and chimpanzee protein-coding isoforms expressed in the frontal cortex and identify 6912 genes that express human unique isoforms. Unexpectedly, more human unique isoforms are detected than those conserved between humans and chimpanzees. Source code and test data of EGIO are available at https://github.com/wu-lab-egio/EGIO. Supplementary data are available at Bioinformatics online.