Fig. 1.

An example of a bulge on eight vertices in a de Bruijn graph (k=4) resulting from a sequencing error. During the process of bulge removal, the correct path (top: CCT-CTA-TAG-AGG-GGA) may be discarded, thus creating a substitution error in the final contig. This may occur if, for example, coverage is taken as a consideration, since the bottom path (CCT-CTT-TTG-TGG-GGA), erroneous in this case, may have higher coverage due to k-mers originating from other parts of the genome