The NR3C1 gene expression is a potential surrogate biomarker for risk and diagnosis of posttraumatic stress disorder

Posttraumatic Stress Disorder (PTSD) is an anxiety disorder which occurs after a traumatic event. The NR3C1 gene codes for the Glucocorticoid Receptor, which participate in the Hypothalamic-Pituitary-Adrenal (HPA) axis and is altered in PTSD patients. To evaluate whether the NR3C1 gene expression in peripheral blood could be useful as a diagnosis biomarker, a total of 32 PTSD patients and 59 healthy controls were analyzed with quantitative RT-PCR. Also, to assess if NR3C1 dysregulation is associated with hypocortisolism in PTSD patients, serum cortisol was quantified by ELISA in a subset of these samples. Significant NR3C1 over-expression was found in PTSD patients compared with controls, and this was higher in patients with acute PTSD. The Area Under the Curve (AUC) of NR3C1 gene expression was 0.797. The sensibility and specificity of NRC1 gene expression to diagnose PTSD was 62.5% and 89.8%, respectively. We also found that an up-regulation of NR3C1 increased the risk for being diagnosed with PTSD (OR= 12.8, 95%, CI 4-41.4). Finally, the NR3C1 gene expression was inversely related with serum cortisol in PTSD patients. The present results suggest that NR3C1 gene expression could be a promising biomarker for PTSD diagnosis and estimate the risk for disease development.