LIQUORICE: detection of epigenetic signatures in liquid biopsies based on whole-genome sequencing data.

Summary:Fragmentation patterns of cell-free DNA reflect the chromatin structure of the cells from which these fragments are derived. Nucleosomes protect the DNA from fragmentation, resulting in decreased sequencing coverage in regions of open chromatin. LIQUORICE is a user-friendly software tool that takes aligned whole-genome sequencing data as input and calculates bias-corrected coverage signatures for predefined, application-specific sets of genomic regions. The tool thereby enables a blood-based analysis of cell death in the body, and it provides a minimally invasive assessment of tumor chromatin states and cell-of-origin. With user-defined sets of regions that exhibit tissue-specific or disease-specific open chromatin, LIQUORICE can be applied to a wide range of detection, classification and quantification tasks in the analysis of liquid biopsies. Availability and implementation:LIQUORICE is freely and openly available as a Python package and command-line tool for UNIX-based systems from bioconda. Documentation, examples and usage instructions are provided at http://liquorice.computational-epigenetics.org. Supplementary information:Supplementary data are available at Bioinformatics Advances online.