The methylation of certain regions in our genome tends to change as we age. These age-sensitive methylation sites can be used to estimate someone’s biological age. We found that individuals with major depressive disorder or a history of childhood trauma may be biologically older than individuals without depression or childhood trauma. These patterns were found in DNA from blood and replicated in DNA from post mortem brain samples.
On average, individuals with major depression or childhood trauma die earlier and have more age-related diseases. Biological age may therefore represent a biomarker to identify patients who may benefit from early interventions seeking to reduce the risk of age-related diseases.