For CAT, although no significant difference was observed between the two groups, there was a tendency towards methylation in the periodontitis group, since the methylated profile was more common amongst these patients (55%=50% partially methylated +5% methylated) when compared with the control group (42.5%=40% partially methylated +2.5% methylated; p=0.077; Table 1 and Figure 3). Here, CAT is linked to periodontitis.