title: An examination of the association between 5-HTTLPR, combat exposure, and PTSD diagnosis among U.S. veterans.
abstract: OBJECTIVE
  To examine the association between the 5-HTTLPR polymorphism of the serotonin transporter (SLC6A4) gene, combat exposure, and posttraumatic stress disorder (PTSD) diagnosis and among two samples of combat-exposed veterans.
  
  
  METHODS
  The first sample included 550 non-Hispanic Black (NHB) combat-exposed veterans. The second sample included 555 non-Hispanic White (NHW) combat-exposed veterans. Participants were genotyped for the 5-HTTLPR/rs25531 variants of the SLC6A4 gene. A structured clinical interview was used to diagnose PTSD. Combat and civilian trauma exposure were assessed with validated self-report instruments. Logistic regression was used to test for main effects of 5-HTTLPR on PTSD diagnosis as well as gene x environment (GxE) interactions after adjusting for sex, ancestry proportion scores, civilian trauma exposure, and combat exposure.
  
  
  RESULTS
  Within the NHB sample, a significant additive effect was observed for 5-HTTLPR (OR = 1.502, p = .0025), such that the odds of having a current diagnosis of PTSD increased by 1.502 for each additional S' allele. No evidence for an association between 5-HTTLPR and PTSD was observed in the NHW sample. In addition, no evidence for combat x 5-HTTLPR effects were observed in either sample.
  
  
  CONCLUSIONS
  The present study suggests that there may be an association between 5-HTTLPR genotype and PTSD diagnosis among NHB veterans; however, no evidence for the hypothesized 5-HTTLPR x combat interaction was found.
authors: Department of Cellular Biology and Anatomy, Georgia Regents University, Augusta, Georgia, United States of America.
authors: Yutao
authors: Y
authors: Liu
authors: Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America.
authors: Melanie E
authors: ME
authors: Garrett
authors: Durham Veterans Affairs Medical Center, Durham, North Carolina, United States of America; VA Mid-Atlantic Mental Illness Research, Education and Clinical Center, Durham, North Carolina, United States of America; Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America.
authors: Michelle F
authors: MF
authors: Dennis
authors: Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America.
authors: Kimberly T
authors: KT
authors: Green
authors: Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America.
authors: Allison E
authors: AE
authors: Ashley-Koch
authors: Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America.
authors: Michael A
authors: MA
authors: Hauser
authors: Durham Veterans Affairs Medical Center, Durham, North Carolina, United States of America; VA Mid-Atlantic Mental Illness Research, Education and Clinical Center, Durham, North Carolina, United States of America; Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America.
authors: Jean C
authors: JC
authors: Beckham
authors: Durham Veterans Affairs Medical Center, Durham, North Carolina, United States of America; VA Mid-Atlantic Mental Illness Research, Education and Clinical Center, Durham, North Carolina, United States of America; Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America.
authors: Nathan A
authors: NA
authors: Kimbrel
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004198:Disease Susceptibility; D005260:Female; D059647:Gene-Environment Interaction; D056726:Genetic Association Studies; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011110:Polymorphism, Genetic; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology*; D014481:United States / Q000453:epidemiology; D014728:Veterans; D000067453:War Exposure
chemical_list: C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins