CHIC: a short read aligner for pan-genomic references

Recently the topic of computational pan-genomics has gained increasing attention, and particularly the problem of moving from a single-reference paradigm to a pan-genomic one. Perhaps the simplest way to represent a pan-genome is to represent it as a set of sequences. While indexing highly repetitive collections has been intensively studied in the computer science community, the research has focused on efficient indexing and exact pattern patching, making most solutions not yet suitable to be used in bioinformatic analysis pipelines. Results: We present CHIC, a short-read aligner that indexes very large and repetitive references using a hybrid technique that combines Lempel-Ziv compression with Burrows-Wheeler read aligners. Availability: Our tool is open source and available online at https://gitlab.com/dvalenzu/CHIC

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