DNA methylation (DNAM) changes in the FKBP5 gene have been identified as a potential molecular mechanism explaining how environmental adversity may confer long-term health risks. However, the neurobiological correlates of epigenetic signatures in FKBP5 have only recently been explored in human brain imaging research. The present study aims to investigate associations of FKBP5 DNAM and functional network architecture during an implicit emotion regulation task (N = 74 healthy individuals). For this, we applied a data-driven multi-voxel pattern analysis (MVPA) to identify regions, where connectivity values vary as a function of FKBP5 DNAM, which then served as seed regions for functional network architecture analyses. Blood-derived DNA samples were obtained to analyze quantitative DNAM at three CpGs sites in intron 7 of the FKBP5 gene using bisulfite pyrosequencing. MPVA revealed a cluster within the right rostral ACC and the paracingulate ACCs, where connectivity patterns were strongly related to FKBP5 DNAM. Using this cluster as seed region for connectivity analyses, we further identified a functional network, including prefrontal, subcortical, insular, and thalamic regions, where connectivity patterns positively correlated with FKBP5 DNAM. A subsequent behavioral domain analyses to determine the functional specialization of this network revealed highest effect sizes for subdomains that represent affective and cognitive processes. Together, these findings suggest that FKBP5 demethylation predicts a widespread functional disruption in a brain network centrally implicated in emotion regulation and cognition, which may in turn convey increased disease susceptibility.
Keywords: ACC; Epigenetics; FKBP5; FMRI; Functional connectivity; MVPA; Methylation.