FKBP5 intron 7 methylation is associated with higher anxiety proneness and smaller right thalamus volume in adolescents.

Dysregulation of stress response systems may mediate the detrimental effects of childhood trauma (CT) on mental health. FKBP5 regulates glucocorticoid receptor sensitivity and exerts pleiotropic effects on intracellular signaling, neurobiology and behavior. We investigated whether CT, alone and in combination with rs1360780 genotype, is associated with altered FKBP5 methylation and whether CT-associated methylation profiles are associated with anxiety proneness (AP) and structural brain volumes. Ninety-four adolescents completed the Childhood Trauma Questionnaire, and a composite AP score was generated from the Childhood Anxiety Sensitivity Index and the State-Trait Anxiety Inventory-Trait measure. Mean methylation values for 12 regulatory regions and 25 individual CpG sites were determined using high-accuracy measurement via targeted bisulfite sequencing. FKBP5 rs1360780 genotype and structural MRI data were available for a subset of participants (n = 71 and n = 75, respectively). Regression models revealed an inverse association between methylation of three intron 7 CpG sites (35558438, 35558566 and 35558710) and right thalamus volume. CpG35558438 methylation was positively associated with AP scores. Our data indicate that an intron 7 methylation profile, consistent with lower FKBP5 expression and elevated high sensitivity glucocorticoid receptor levels, is associated with higher AP and smaller right thalamus volume. Research into the mechanisms underlying the intron 7 methylation-thalamus volume relationship, and whether it confers increased risk for long-term psychopathology by altering the regulatory threshold of stress responding, is required.