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.