P. gingivalis core genome. Pie diagram representing all probes included in the results divided into pieces representing the conserved core genome, aberrant core genome and the variable genes. The percentages show the proportions of the total of functional probes. 80% of the strain W83 genes is present and conserved among the test strains. 6% of the W83 genes is present but aberrant and 13% of the genes is absent in at least one of the test strains. Two probes with very low signals were found as non-aberrant but absent.