Abstract: Personality traits are thought to be endophenotypes (high Harm Avoidance (HA), low Self-directedness (SD)) for most psychiatric disorders and predictors of life outcomes. Genetic influences on personality traits are attributable to many genes of small effect and are modulated by environmental factors. We aimed to examine gene-environment (GxE) and gene-gene (GxG) interaction models based on neurotrophic factor (NGF, BDNF, NTRK2, NTRK3), serotoninergic (SLC6A4, TPH1) and dopaminergic system (DRD2, SLC6A3) gene polymorphisms contributing into personality traits variation in healthy individuals.
In total, 1018 healthy individuals (68% women) from Russia (mean age±SD: 19.81±2.65 years) without any history of psychopathologies were subjected to personality traits assessment via TCI-125 (Cloninger et al., 1993). Involved individuals are Caucasians from Russian (N=409), Tatar (N=290), Bashkir (N=130) and Udmurt populations (N=189). Socio-demographic data including gender, ethnicity, order and season of birth (SOB), place of residence, level of income, childhood maltreatment were obtained. Genotyping of 70 SNPs was performed with SNPlexTM platform (Applied Biosystems). Statistical analysis was conducted with PLINK v.1.07 corrected via FDR-procedure for multiple comparisons.
The present study revealed GxE models demonstrated BDNF Val66Met*SOB (PFDR=0.036), BDNF rs1519479*ethnicity (PFDR=0.042) and 5-HTTLPR*SOB (PFDR=0.05) interactions affected HA. Moreover, variations in SD were caused by interactions between BDNF Val66Met (PFDR=0.048), BDNF rs2030323 (PFDR=0.035) and ethnicity. Accordingly, genetic testing for BDNF and 5-HTT gene polymorphisms assuming gender, ethnicity and SOB confounding is necessary for psychopathologies prevention at early stages. This work was supported by Russian foundation for humanities grant 13-06-00583a.