Antidepressant Exposure and DNA Methylation: Insights from a Methylome-Wide Association Study

Area of Science:

• Epigenetics
• Psychiatry
• Genomics

Background:

• Understanding antidepressant mechanisms is crucial for developing more effective and tolerable treatments.
• DNA methylation (DNAm) changes associated with antidepressant exposure require identification.

Approach:

• Methylome-wide association studies (MWAS) were conducted on blood samples from Generation Scotland (GS) and the Netherlands Study of Depression and Anxiety (NESDA).
• A methylation profile score (MPS) was derived and validated across eight independent cohorts.
• Analyses included testing for enrichment in specific tissues, gene ontologies, and independent MWAS datasets.

Key Points:

• Significant hypermethylation was observed at seven DNAm sites (self-report) and four sites (prescription-derived) in MWAS.
• The top locus, cg26277237 (KANK1), showed strong association (p=9.3x10^-13).
• A methylation profile score (MPS) was significantly associated with antidepressant exposure in a meta-analysis of external cohorts (p < 1x10^-4).

Conclusions:

• Antidepressant exposure is associated with differential DNAm in whole blood across multiple cohorts.
• Hypermethylation at KANK1 and DGUOK-AS1, genes involved in mitochondrial metabolism and neurite outgrowth, was identified.
• Further research into these DNAm changes could identify novel targets for antidepressant therapies.