title: Epigenetic alterations of the BDNF gene in combat-related post-traumatic stress disorder.
abstract: OBJECTIVE
  Brain-derived neurotrophic factor (BDNF) plays a crucial role in modulating resilience and vulnerability to stress. The aim of this study was to investigate whether epigenetic regulation of the BDNF gene is a biomarker of post-traumatic stress disorder (PTSD) development among veterans exposed to combat in the Vietnam War.
  
  
  METHODS
  Using the Clinician-Administered PTSD Scale, combat veterans were grouped into those with (n = 126) and without (n = 122) PTSD. DNA methylation levels at four CpG sites within the BDNF promoter I region were quantified in the peripheral blood using pyrosequencing. The effects of BDNF DNA methylation levels and clinical variables on the diagnosis of PTSD were tested using binary logistic regression analysis.
  
  
  RESULTS
  Subjects with PTSD showed a higher DNA methylation of four CpG sites at the BDNF promoter compared with those without PTSD. High methylation levels at the BDNF promoter CpG site, high combat exposure, and alcohol problems were significantly associated with PTSD diagnosis.
  
  
  CONCLUSIONS
  This study demonstrated an association between higher DNA methylation of the BDNF promoter and PTSD diagnosis in combat-exposed individuals. Our findings suggest that altered BDNF methylation may be a valuable biomarker of PTSD after trauma exposure.
authors.affiliation: Department of Neuropsychiatry, Veterans Health Service Medical Center, Seoul, South Korea.
authors.forename: T Y
authors.initials: TY
authors.lastname: Kim
authors.affiliation: Department of Psychiatry and Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: S J
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Neuropsychiatry, Veterans Health Service Medical Center, Seoul, South Korea.
authors.forename: H G
authors.initials: HG
authors.lastname: Chung
authors.affiliation: Department of Neuropsychiatry, Veterans Health Service Medical Center, Seoul, South Korea.
authors.forename: J H
authors.initials: JH
authors.lastname: Choi
authors.affiliation: Department of Psychiatry and Institute of Clinical Psychopharmacology, Dongguk University Ilsan Hospital, Goyang, Gyeonggi, South Korea.
authors.forename: S H
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Psychiatry and Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: J I
authors.initials: JI
authors.lastname: Kang
mesh_terms: D000368:Aged; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D003130:Combat Disorders / Q000175:diagnosis* / Q000235:genetics; D018899:CpG Islands; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011401:Promoter Regions, Genetic; D011569:Psychiatric Status Rating Scales
chemical_list: D019208:Brain-Derived Neurotrophic Factor; C579455:BDNF protein, human
keywords: 
  BDNF
  ; DNA methylation; epigenetics; post-traumatic stress disorder; trauma