ASSOCIATIONS BETWEEN POLYMORPHISMS IN THE SOLUTE CARRIER FAMILY 6 MEMBER 3 AND THE MYELIN BASIC PROTEIN GENE AND POSTTRAUMATIC STRESS DISORDER

Background: Previous research showed inconsistent results concerning a possible association between solute carrier family 6 member 3 (SLC6A3) gene polymorphisms and dopamine symptoms of posttraumatic stress disorder (PTSD). Several studies also indicate that the myelin basic protein (MBP) gene is of importance in the etiology of several psychiatric disorders. The aim of this study was to investigate the relation of distinct SLC6A3 and MBP gene polymorphisms with PTSD and whether SLC6A3 and MBP genotypes contribute to PTSD symptom severity. Subjects and methods: The study included 719 individuals who had experienced war trauma in the South Eastern Europe (SEE). Genotypes of variable number tandem repeat (VNTR) polymorphism within the SLC6A3 gene were assessed in 696 participants, and the single nucleotide polymorphism (SNP) rs12458282 located within the MBP gene region was genotyped in a total of 703 subjects. The Mini International Neuropsychiatric Interview, the Clinical Administrated PTSD Scale (CAPS) and Brief Symptom Inventory (BSI), were used for data collection. Results: No significant differences concerning the investigated SLC6A3 and MBP polymorphisms was identifiable between PTSD and non PTSD participants. Also we could not detect significant influence of these distinct SLC6A3 and MBP alleles on the severity of PTSD symptoms (CAPS) or BSI scores. However, the results of MBP rs12458282 within the patients with lifetime PTSD may point to a possible correlation of the major allele (T) with elevated CAPS scores. Conclusions: Our results do not support an association of the analysed SLC6A3 and MBP gene polymorphisms with PTSD in war traumatized individuals. We found that there is a possibility for a correlation of the T allele rs12458282 within the MBP gene with higher CAPS scores in lifetime PTSD patients which would need to be tested in a sample providing more statistical power

ROLE OF THE ALLELIC VARIATION IN THE 5-HYDROXYTRYPTAMINE RECEPTOR 1A (HTR1A) AND THE TRYPTOPHAN HYDROXYLASE 2 (TPH2) GENES IN THE DEVELOPMENT OF PTSD

Background: Post-traumatic stress disorder (PTSD) is a stress related disorder which can occur in an individual after exposure to a traumatic event. It most commonly co-occurs with depression. The two disorders share not only overlapping symptoms, but also genetic diathesis. The aim of this study was to investigate the potential role of single nucleotide polymorphisms (SNPs) of the two serotonergic candidate genes 5-hydroxytryptamine receptor 1A (HTR1A) and tryptophan hydroxylase 2 (TPH2) in the pathogenesis of PTSD and comorbid psychopathology. Subjects and methods: 719 (487 males, 232 females) participants who had experienced war-related trauma between 1991 and 1999 in Bosnia and Herzegovina, Kosovo and Croatia were included in the study. The Sociodemographic questionnaire, Mini International Neuropsychiatric Interview (M.I.N.I.), Clinician Administered PTSD Scale (CAPS) and Brief Symptom Inventory (BSI) were used to collect clinical data. The SNPs rs6295 (HTR1A), rs11178997 and rs1386494 (TPH2) were investigated for their association with PTSD and comorbid psychopathology. Results: A nominal significant association was found between the BSI total score in Lifetime PTSD with the SNP rs6295 of the HTR1A gene. The best result was seen in the dominant model (P=0.018), with the minor allele (C) being the risk allele. Several BSI subscores were also associated with the minor (C) allele in Lifetime PTSD. No association was found for the TPH2 SNPs rs11178997 and rs1386494 in relation to PTSD or comorbid psychopathology. Conclusions: Our findings suggest that rs6295 in the HTR1A gene may contribute to the psychopathology of PTSD

Association of polygenic risk scores, traumatic life events and coping strategies with war-related PTSD diagnosis and symptom severity in the South Eastern Europe (SEE)-PTSD cohort

Objectives Posttraumatic stress disorder (PTSD) is triggered by extremely stressful environmental events and characterized by high emotional distress, re-experiencing of trauma, avoidance and hypervigilance. The present study uses polygenic risk scores (PRS) derived from the UK Biobank (UKBB) mega-cohort analysis as part of the PGC PTSD GWAS effort to determine the heritable basis of PTSD in the South Eastern Europe (SEE)-PTSD cohort. We further analyzed the relation between PRS and additional disease-related variables, such as number and intensity of life events, coping, sex and age at war on PTSD and CAPS as outcome variables. Methods Association of PRS, number and intensity of life events, coping, sex and age on PTSD were calculated using logistic regression in a total of 321 subjects with current and remitted PTSD and 337 controls previously subjected to traumatic events but not having PTSD. In addition, PRS and other disease-related variables were tested for association with PTSD symptom severity, measured by the Clinician Administrated PTSD Scale (CAPS) by liner regression. To assess the relationship between the main outcomes PTSD diagnosis and symptom severity, each of the examined variables was adjusted for all other PTSD related variables. Results The categorical analysis showed significant polygenic risk in patients with remitted PTSD and the total sample, whereas no effects were found on symptom severity. Intensity of life events as well as the individual coping style were significantly associated with PTSD diagnosis in both current and remitted cases. The dimensional analyses showed as association of war-related frequency of trauma with symptom severity, whereas the intensity of trauma yielded significant results independently of trauma timing in current PTSD. Conclusions The present PRS application in the SEE-PTSD cohort confirms modest but significant polygenic risk for PTSD diagnosis. Environmental factors, mainly the intensity of traumatic life events and negative coping strategies, yielded associations with PTSD both categorically and dimensionally with more significant p-values. This suggests that, at least in the present cohort of war-related trauma, the association of environmental factors and current individual coping strategies with PTSD psychopathology was stronger than the polygenic risk