Sex differences in epigenetic mechanisms may underlie risk and resilience for mental health disorders.

Alterations in the epigenetic programming of sex differences in the brain may underlie sexually dimorphic neurodevelopmental disorders. Sex differences have been found in DNA methyltransferase 3a, DNA methylation patterns, MeCP2 and nuclear co-repressors within the developing brain. Variations in these epigenetic mechanisms can have profound consequences on gene expression and brain function. Exogenous or endogenous perturbations during development that impact these epigenetic processes can alter the developmental trajectory of the brain. These alterations may confer sexually dimorphic risk and resilience for developing a neurological or mental health disorder. For example, one possibility is that the male brain may be less able to adapt to reductions in MeCP2 levels placing males at higher risk for autism spectrum disorders.