DRD2 and Borderline personality disorder: Impact of BPD: Significant group effect of methylation levels with BPD status. Mean methylation levels of DRD2 in BSD/BPD subjects were significantly increased compared to NE, and marginally significant increased compared to BSD/non-BPD. No significant differences between total BSD and NE. Slightly significant (by trend) higher methylation of BSD/SA than NE (but not of BSD/PA).