Death by suicide and suicidal behavior are major concerns among U.S. military veterans; however, no genome-wide association studies (GWAS) studies of suicidal behavior have been conducted among U.S. military veterans to date, despite the elevated rate of suicidal behavior observed within this population. Accordingly, the primary objective of the present research was to conduct the first GWAS of suicide attempts and suicidal ideation in a large and well-characterized sample of U.S. military veterans. The gene most significantly associated (p=9.28×10(−7)) with suicide attempts was the Potassium Calcium-Activated Channel Subfamily M Regulatory Beta Subunit 2 (KCNMB2) gene, which plays a key role in neuronal excitability. In addition, replication analyses provided additional support for the potential role of the ABI Family Member 3 Binding Protein (ABI3BP) gene in the pathogenesis of suicidal behavior, as numerous nominal associations were found between this gene and both suicide attempts and suicidal ideation. Additional work aimed at replicating and extending these findings is needed.
Depending on the traumatic event, a significant fraction of trauma survivors subsequently develop PTSD. The additional variability in PTSD risk is expected to arise from genetic susceptibility. Unfortunately, several genome-wide association studies (GWAS) have failed to identify a consistent genetic marker for PTSD. The heritability of intermediate phenotypes such as regional brain volumes is often 80% or higher. We conducted a GWAS of subcortical brain volumes in a sample of recent military veteran trauma survivors (n = 157), grouped into PTSD (n = 66) and non-PTSD controls (n = 91). Covariates included PTSD diagnosis, sex, intracranial volume, ancestry, childhood trauma, SNP×PTSD diagnosis, and SNP×childhood trauma. We identified several genetic markers in high linkage disequilibrium (LD) with rs9373240 (p = 2.0 × 10−7, FDR q = 0.0375) that were associated with caudate volume. We also observed a significant interaction between rs9373240 and childhood trauma (p-values = 0.0007–0.002), whereby increased trauma exposure produced a stronger association between SNPs and increased caudate volume. We identified several SNPs in high LD with rs34043524, which is downstream of the TRAM1L1 gene that were associated with right lateral ventricular volume (p = 1.73 × 10−7; FDR q = 0.032) and were also associated with lifetime alcohol abuse or dependence (p = 2.49 × 10−7; FDR q = 0.0375). Finally, we identified several SNPs in high LD with rs13140180 (p = 2.58 × 10−7; FDR q = .0016), an intergenic region on chromosome 4, and several SNPs in the TMPRSS15 associated with right nucleus accumbens volume (p = 2.58 × 10−7; FDR q = 0.017). Both TRAM1L1 and TMPRSS15 have been previously implicated in neuronal function. Key results survived genome-wide multiple-testing correction in our sample. Leveraging neuroimaging phenotypes may offer a shortcut, relative to clinical phenotypes, in mapping the genetic architecture and neurobiological pathways of PTSD.
In: Logue , M W , Miller , M W , Wolf , E J , Huber , B R , Morrison , F G , Zhou , Z , Zheng , Y , Smith , A K , Daskalakis , N P , Ratanatharathorn , A , Uddin , M , Nievergelt , C M , Ashley-Koch , A E , Baker , D G , Beckham , J C , Garrett , M E , Boks , M P , Geuze , E , Grant , G A , Hauser , M A , Kessler , R C , Kimbrel , N A , Maihofer , A X , Marx , C E , Qin , X-J , Risbrough , V B , Rutten , B P F , Stein , M B , Ursano , R J , Vermetten , E , Vinkers , C H , Ware , E B , Stone , A , Schichman , S A , McGlinchey , R E , Milberg , W P , Hayes , J P , Verfaellie , M & Traumatic Stress Brain Study Group 2020 , ' An epigenome-wide association study of posttraumatic stress disorder in US veterans implicates several new DNA methylation loci ' , Clinical epigenetics , vol. 12 , no. 1 , 46 . https://doi.org/10.1186/s13148-020-0820-0
Background Previous studies using candidate gene and genome-wide approaches have identified epigenetic changes in DNA methylation (DNAm) associated with posttraumatic stress disorder (PTSD). Methods In this study, we performed an EWAS of PTSD in a cohort of Veterans (n = 378 lifetime PTSD cases and 135 controls) from the Translational Research Center for TBI and Stress Disorders (TRACTS) cohort assessed using the Illumina EPIC Methylation BeadChip which assesses DNAm at more than 850,000 sites throughout the genome. Our model included covariates for ancestry, cell heterogeneity, sex, age, and a smoking score based on DNAm at 39 smoking-associated CpGs. We also examined in EPIC-based DNAm data generated from pre-frontal cortex (PFC) tissue from the National PTSD Brain Bank (n = 72). Results The analysis of blood samples yielded one genome-wide significant association with PTSD at cg19534438 in the gene G0S2 (p = 1.19 x 10(-7), p(adj) = 0.048). This association was replicated in an independent PGC-PTSD-EWAS consortium meta-analysis of military cohorts (p = 0.0024). We also observed association with the smoking-related locus cg05575921 in AHRR despite inclusion of a methylation-based smoking score covariate (p = 9.16 x 10(-6)), which replicates a previously observed PGC-PTSD-EWAS association (Smith et al. 2019), and yields evidence consistent with a smoking-independent effect. The top 100 EWAS loci were then examined in the PFC data. One of the blood-based PTSD loci, cg04130728 in CHST11, which was in the top 10 loci in blood, but which was not genome-wide significant, was significantly associated with PTSD in brain tissue (in blood p = 1.19 x 10(-5), p(adj) = 0.60, in brain, p = 0.00032 with the same direction of effect). Gene set enrichment analysis of the top 500 EWAS loci yielded several significant overlapping GO terms involved in pathogen response, including "Response to lipopolysaccharide" (p = 6.97 x 10(-6), p(adj) = 0.042). Conclusions The cross replication observed in independent cohorts is evidence that ...
Epigenetic differences may help to distinguish between PTSD cases and trauma-exposed controls. Here, we describe the results of the largest DNA methylation meta-analysis of PTSD to date. Ten cohorts, military and civilian, contribute blood-derived DNA methylation data from 1,896 PTSD cases and trauma-exposed controls. Four CpG sites within the aryl-hydrocarbon receptor repressor (AHRR) associate with PTSD after adjustment for multiple comparisons, with lower DNA methylation in PTSD cases relative to controls. Although AHRR methylation is known to associate with smoking, the AHRR association with PTSD is most pronounced in non-smokers, suggesting the result was independent of smoking status. Evaluation of metabolomics data reveals that AHRR methylation associated with kynurenine levels, which are lower among subjects with PTSD. This study supports epigenetic differences in those with PTSD and suggests a role for decreased kynurenine as a contributor to immune dysregulation in PTSD.
In: Smith , A K , Ratanatharathorn , A , Maihofer , A X , Naviaux , R K , Aiello , A E , Amstadter , A B , Ashley-Koch , A E , Baker , D G , Beckham , J C , Boks , M P , Bromet , E , Dennis , M , Galea , S , Garrett , M E , Geuze , E , Guffanti , G , Hauser , M A , Katrinli , S , Kilaru , V , Kessler , R C , Kimbrel , N A , Koenen , K C , Kuan , P-F , Li , K , Logue , M W , Lori , A , Luft , B J , Miller , M W , Naviaux , J C , Nugent , N R , Qin , X , Ressler , K J , Risbrough , V B , Rutten , B P F , Stein , M B , Ursano , R J , Vermetten , E , Vinkers , C H , Wang , L , Youssef , N A , Uddin , M , Nievergelt , C M , INTRuST Clinical Consortium , VA Mid-Atlantic MIRECC Workgroup & PGC PTSD Epigenetics Workgroup 2020 , ' Epigenome-wide meta-analysis of PTSD across 10 military and civilian cohorts identifies methylation changes in AHRR ' , Nature Communications , vol. 11 , no. 1 , 5965 . https://doi.org/10.1038/s41467-020-19615-x
Epigenetic differences may help to distinguish between PTSD cases and trauma-exposed controls. Here, we describe the results of the largest DNA methylation meta-analysis of PTSD to date. Ten cohorts, military and civilian, contribute blood-derived DNA methylation data from 1,896 PTSD cases and trauma-exposed controls. Four CpG sites within the aryl-hydrocarbon receptor repressor (AHRR) associate with PTSD after adjustment for multiple comparisons, with lower DNA methylation in PTSD cases relative to controls. Although AHRR methylation is known to associate with smoking, the AHRR association with PTSD is most pronounced in non-smokers, suggesting the result was independent of smoking status. Evaluation of metabolomics data reveals that AHRR methylation associated with kynurenine levels, which are lower among subjects with PTSD. This study supports epigenetic differences in those with PTSD and suggests a role for decreased kynurenine as a contributor to immune dysregulation in PTSD. PTSD has been associated with DNA methylation of specific loci in the genome, but studies have been limited by small sample sizes. Here, the authors perform a meta-analysis of DNA methylation data from 10 different cohorts and identify CpGs in AHRR that are associated with PTSD.
Epigenetic differences may help to distinguish between PTSD cases and trauma-exposed controls. Here, we describe the results of the largest DNA methylation meta-analysis of PTSD to date. Ten cohorts, military and civilian, contribute blood-derived DNA methylation data from 1,896 PTSD cases and trauma-exposed controls. Four CpG sites within the aryl-hydrocarbon receptor repressor (AHRR) associate with PTSD after adjustment for multiple comparisons, with lower DNA methylation in PTSD cases relative to controls. Although AHRR methylation is known to associate with smoking, the AHRR association with PTSD is most pronounced in non-smokers, suggesting the result was independent of smoking status. Evaluation of metabolomics data reveals that AHRR methylation associated with kynurenine levels, which are lower among subjects with PTSD. This study supports epigenetic differences in those with PTSD and suggests a role for decreased kynurenine as a contributor to immune dysregulation in PTSD.
Epigenetic differences may help to distinguish between PTSD cases and trauma-exposed controls. Here, we describe the results of the largest DNA methylation meta-analysis of PTSD to date. Ten cohorts, military and civilian, contribute blood-derived DNA methylation data from 1,896 PTSD cases and trauma-exposed controls. Four CpG sites within the aryl-hydrocarbon receptor repressor (AHRR) associate with PTSD after adjustment for multiple comparisons, with lower DNA methylation in PTSD cases relative to controls. Although AHRR methylation is known to associate with smoking, the AHRR association with PTSD is most pronounced in non-smokers, suggesting the result was independent of smoking status. Evaluation of metabolomics data reveals that AHRR methylation associated with kynurenine levels, which are lower among subjects with PTSD. This study supports epigenetic differences in those with PTSD and suggests a role for decreased kynurenine as a contributor to immune dysregulation in PTSD.
In: Smith , A K , Ratanatharathorn , A , Maihofer , A X , Naviaux , R K , Aiello , A E , Amstadter , A B , Ashley-Koch , A E , Baker , D G , Beckham , J C , Boks , M P , Bromet , E , Dennis , M , Galea , S , Garrett , M E , Geuze , E , Guffanti , G , Hauser , M A , Katrinli , S , Kilaru , V , Kessler , R C , Kimbrel , N A , Koenen , K C , Kuan , P F , Li , K , Logue , M W , Lori , A , Luft , B J , Miller , M W , Naviaux , J C , Nugent , N R , Qin , X , Ressler , K J , Risbrough , V B , Rutten , B P F , Stein , M B , Ursano , R J , Vermetten , E , Vinkers , C H , Wang , L , Youssef , N A , Marx , C , Grant , G , Stein , M , Qin , X J , Jain , S , McAllister , T W , Zafonte , R , Lang , A , Coimbra , R , Andaluz , N , Shutter , L , George , M S , Brancu , M , Calhoun , P S , Dedert , E , Elbogen , E B , Fairbank , J A , Hurley , R A , Kilts , J D , Kirby , A , Marx , C E , McDonald , S D , Moore , S D , Morey , R A , Naylor , J C , Rowland , J A , Swinkels , C , Szabo , S T , Taber , K H , Tupler , L A , Van Voorhees , E E , Yoash-Gantz , R E , Basu , A , Brick , L A , Dalvie , S , Daskalakis , N P , Ensink , J B M , Hemmings , S M J , Herringa , R , Ikiyo , S , Koen , N , Kuan , P F , Montalvo-Ortiz , J , Nispeling , D , Pfeiffer , J , Qin , X J , Ressler , K J , Schijven , D , Seedat , S , Shinozaki , G , Sumner , J A , Swart , P , Tyrka , A , Van Zuiden , M , Wani , A , Wolf , E J , Zannas , A , Uddin , M , Nievergelt , C M , INTRuST Clinical Consortium , VA Mid-Atlantic MIRECC Workgroup & PGC PTSD Epigenetics Workgroup 2020 , ' Epigenome-wide meta-analysis of PTSD across 10 military and civilian cohorts identifies methylation changes in AHRR ' , Nature Communications , vol. 11 , no. 1 , 5965 . https://doi.org/10.1038/s41467-020-19615-x
Epigenetic differences may help to distinguish between PTSD cases and trauma-exposed controls. Here, we describe the results of the largest DNA methylation meta-analysis of PTSD to date. Ten cohorts, military and civilian, contribute blood-derived DNA methylation data from 1,896 PTSD cases and trauma-exposed controls. Four CpG sites within the aryl-hydrocarbon receptor repressor (AHRR) associate with PTSD after adjustment for multiple comparisons, with lower DNA methylation in PTSD cases relative to controls. Although AHRR methylation is known to associate with smoking, the AHRR association with PTSD is most pronounced in non-smokers, suggesting the result was independent of smoking status. Evaluation of metabolomics data reveals that AHRR methylation associated with kynurenine levels, which are lower among subjects with PTSD. This study supports epigenetic differences in those with PTSD and suggests a role for decreased kynurenine as a contributor to immune dysregulation in PTSD.