Fig. 1.

Illustration of the QUOD method using a fictional dataset. On the left side, genes are classified as ‘core’ (dark blue) or ‘dispensable’ (dark grey) according to a cutoff. On the right side, gene dispensability is quantified according to a dispensability score based on the normalised coverage in a read mapping (I–X: investigated genomes). Coloring of genes (right side) indicates different dispensability scores. Extremely rare genes, which are absent from most genomes but present in the reference, can be easily detected using QUOD