NR3C1 and major depressive disorder: Consistent with our results, some studies show HV reductions in adolescents at risk of developing MDD even before clinical manifestation of the disease.37, 38 Recent findings show associations between hippocampal volume abnormalities and several mechanisms involved in stress-related disorders and MDD, such as the messenger RNA expression of glucocorticoid inducible genes,71 glucocorticoid receptor methylation,72 genetic polymorphisms associated with variation in pro-inflammatory cytokine levels73 and increased oxidative stress.49