Allowing Mismatches in Anchors for Whole Genome Alignment

Recent work on whole genome alignment has resulted in efficient tools to locate (possibly) conserved regions of two genomic sequences. Most of such tools start with locating a set of short and highly similar substrings (called anchors) that are present in both genomes. These anchors provide clues for the conserved regions, and the effectiveness of the tools is highly related to the quality of the anchors. Some popular software tools use the exact match maximal unique substrings (EM-MUM) as anchors. However, the result is not satisfactory especially for genomes with high mutation rates (e.g. virus). In our experiments, we found that more than 40% of the conserved genes are not recovered. In this paper, we consider anchors with mismatches in order to increase the effectiveness of locating conserved regions. Key-Words: Whole genome alignment, anchors with mismatches, conserved regions