The interaction between DRD4 gene rs1800955 polymorphism and negative life events on the personality characteristics of Mongolian adolescents

Objective To investigate the interaction between rs1800955 polymorphism of dopamine D4 receptor(DRD4) gene and negative life events on personality characteristics of Mongolian adolescents. Methods A total of 239 Mongolian adolescents aged 12-15 were assessed with Eysenck Personality Questionnaire(EPQ) and Adolescent Self-Rating Life Events Check List(ASLEC). The polymorphism of DRD4 gene rs1800955 was determined by improved multiple ligase detection reaction(iMLDR) technique. Results (1) The rs1800955 polymorphism of DRD4 gene was significantly correlated with psychoticism score of EPQ.The psychoticism score of individuals with CC genotype (4.94 ± 3.19) was higher than that of TT genotype (3.38±2.29), and the difference was statistically significant (P<0.05). (2) The scores of psychoticism and neuroticism in Mongolian adolescents were positively correlated with the factors of negative life events(r=0.154-0.375, P<0.05 or 0.01) .(3) The interaction between the rs1800955 polymorphism of DRD4 gene and negative life events significantly affected the scores of psychoticism in Mongolian adolescents (CC genotype x interpersonal factor: B=-2.689, 95%CI=-4.589--0.789, χ2=7.695, P<0.01). In individuals with CC genotype, the scores of psychoticism in those with high scores of interpersonal relationship factors were significantly higher than those with low scores of interpersonal relationship factors((3.01±0.71) vs (2.61±0.67); t=-3.066, P<0.01). Conclusion The polymorphism of DRD4 gene rs1800955 and its association with interpersonal factors play an important role in the psychoticism of Mongolian adolescents.The CC genotype is a risk factor of psychoticism, and the poor interpersonal relationship may increase the risk of individuals with CC genotype. Key words: Mongolian adolescents; Dopamine D4 receptor gene; rs1800955 polymorphisms; Negative life events; Personality characteristics