Yes, your body does something called methylation to alter gene expression, and yes, medicine is trying to use this fact for diagnostics at the moment. If you e

Yes, your body does something called methylation to alter gene expression, and yes, medicine is trying to use this fact for diagnostics at the moment. If you experience stress, your body will upregulate expression of cortisol and other hormones. If you remove the stressor, it will downregulate. Chronic stress can break these processes and require medical intervention. This is all (in theory) detectable with methylation analysis of the genome, but it will take a decade to fully flesh the technology out.