title: Early life stress combined with serotonin 3A receptor and brain-derived neurotrophic factor valine 66 to methionine genotypes impacts emotional brain and arousal correlates of risk for depression.
abstract: BACKGROUND
  Depression will be the second largest burden of disease by 2020. Developing new tools for identifying risk and ultimately prevention of depression relies on elucidating the integrative relationships between susceptibility markers from gene-stress interactions and how they impact emotional brain and arousal systems. They have largely been studied in isolation.
  
  
  METHODS
  We examined how genetic (brain-derived neurotrophic factor [BDNF] valine 66 to methionine [Val66Met] and serotonin receptor gene 3A [HTR3A]) and early life stress susceptibility factors interact in predicting electroencephalogram (EEG) asymmetry, emotion-elicited heart rate, and self-reported negativity bias, each correlates of risk for depression. Caucasian volunteers (n = 363) were derived from the Brain Resource International Database, via the Brain Research And Integrative Neuroscience Network.
  
  
  RESULTS
  Individuals with both BDNF methionine and HTR3A CC risk genotypes and early life stressors demonstrated a profile of elevated emotion-elicited heart rate and right frontal hyper-activation with right parietotemporal hypoactivation in EEG asymmetry. Elevations in heart rate were a moderator of negativity bias.
  
  
  CONCLUSIONS
  The findings provide new evidence that these gene-stress susceptibility factors contribute to a brain-arousal profile indicative of risk for depression. They are a step toward identifying biological markers for detecting risk before overt symptoms. It would be valuable for future studies to examine comorbidity and specificity issues; for instance, whether these gene-stress factors contribute in different ways to the partially distinct EEG asymmetry profiles found with anxiety.
authors: Brain Dynamics Center, University of Sydney Medical School and Westmead Millennium Institute, Australia.
authors: Justine M
authors: JM
authors: Gatt
authors: Charles B
authors: CB
authors: Nemeroff
authors: Peter R
authors: PR
authors: Schofield
authors: Robert H
authors: RH
authors: Paul
authors: C Richard
authors: CR
authors: Clark
authors: Evian
authors: E
authors: Gordon
authors: Leanne M
authors: LM
authors: Williams
mesh_terms: D000328:Adult; D001143:Arousal / Q000235:genetics*; D058256:Brain Waves / Q000235:genetics / Q000502:physiology; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D003863:Depression / Q000235:genetics* / Q000503:physiopathology / Q000523:psychology*; D004569:Electroencephalography; D004644:Emotions / Q000502:physiology*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics / Q000523:psychology; D005838:Genotype; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008715:Methionine / Q000235:genetics; D011110:Polymorphism, Genetic; D044406:Receptors, Serotonin, 5-HT3 / Q000235:genetics*; D013315:Stress, Psychological / Q000235:genetics / Q000523:psychology*; D014633:Valine / Q000235:genetics
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D044406:Receptors, Serotonin, 5-HT3; D008715:Methionine; D014633:Valine