Sample mutation mapping data Figure 1 Sample mutation mapping data. The ratio of signal of W3110 vs. MG1655 is shown for probes spaced every ~7 bp surrounding an IS5 insertion in dcuC (top), a SNP in ycdT (middle), and a SNP in acnA (bottom). acnA region structure and with sequences repeated multiple times in the genome [15] [17] . In addition, detection of SNPs may be less accurate in areas with low overall intensity. Fortunately, such regions are relatively uncommon, and CGS appears to detect most mutations with a reasonable degree of confidence.