Motivation: Genomics has revolutionised biological research, but quality assessment of the resulting assembled sequences is complicated and remains mostly limited to technical measures like N50.

Results: We propose a measure for quantitative assessment of genome assembly and annotation completeness based on evolutionarily informed expectations of gene content. We implemented the assessment procedure in open-source software, with sets of Benchmarking Universal Single-Copy Orthologs, named BUSCO.

Availability and Implementation: Software implemented in Python and datasets available for download from http://busco.ezlab.org.

Contact: Evgeny.Zdobnov@unige.ch