ARBitR: An overlap-aware genome assembly scaffolder for linked reads

10X Genomics Chromium linked reads contain information that can be used to link sequences together into scaffolds in draft genome assemblies. Existing software for this purpose perform the scaffolding by joining sequences together with a gap between them, not considering potential contig overlaps. Such overlaps can be particularly prominent in genome drafts assembled from long-read sequencing data where an overlap-layout-consensus (OLC) algorithm has been used. Ignoring overlapping contig ends may result in genes and other features being incomplete or fragmented in the resulting scaffolds. We developed the application ARBitR to generate scaffolds from genome drafts using 10X Chromium data, with a focus on minimizing the number of gaps in resulting scaffolds by incorporating an OLC step to resolve junctions between linked contigs. We tested the performance of ARBitR on three published and simulated datasets and compared to the previously published tools ARCS and ARKS. The results revealed that ARBitR performed similarly considering contiguity statistics, and the advantage of the overlapping step was revealed by fewer long and short variants in ARBitR produced scaffolds, in addition to a higher proportion of completely assembled LTR retrotransposons. We expect ARBitR to have broad applicability in genome assembly projects that utilize 10X Chromium linked reads. Availability and implementationARBitR is written and implemented in Python3 for Unix-like operative systems. All source code is available at https://github.com/markhilt/ARBitR under the GNU General Public License v3. Contactmarkus.hiltunen@ebc.uu.se Supplementary informationavailable online