Arriba is a command-line tool for the detection of gene fusions from RNA-Seq data. It was developed for the use in a clinical research setting. Therefore, short runtimes and high sensitivity were important design criteria. It is based on the ultrafast STAR aligner and the post-alignment runtime is typically just ~2 minutes. In contrast to many other fusion detection tools which build on STAR, Arriba does not require to reduce the alignIntronMax parameter of STAR to detect fusions arising from focal deletions.

Apart from gene fusions, Arriba can detect other structural rearrangements with potential clinical relevance, such as viral integration sites, internal tandem duplications, whole exon duplications, truncations of genes (i.e., breakpoints in introns and intergenic regions).

Arriba is the winner of the DREAM SMC-RNA Challenge, an international competition organized by ICGC, TCGA, IBM, and Sage Bionetworks to determine the current gold standard for the detection of gene fusions from RNA-Seq data. The final results of the challenge are posted on the Round 5 Leaderboard and discussed in the accompanying publication.

Code repository

The source code of Arriba is maintained on GitHub.

Get help

Use the GitHub issue tracker to get help or to report bugs.


Sebastian Uhrig, Julia Ellermann, Tatjana Walther, Pauline Burkhardt, Martina Fröhlich, Barbara Hutter, Umut H. Toprak, Olaf Neumann, Albrecht Stenzinger, Claudia Scholl, Stefan Fröhling and Benedikt Brors: Accurate and efficient detection of gene fusions from RNA sequencing data. Genome Research. March 2021 31: 448-460; Published in Advance January 13, 2021. doi: 10.1101/gr.257246.119


The code, software and database files of Arriba are distributed under the MIT/Expat License, with the exception of the script draw_fusions.R, which is distributed under the GNU GPL v3 due to dependencies on GPL-licensed R packages. The terms and conditions of both licenses can be found in the LICENSE file.