Abstract:

Parent-child relationship has been a longstanding theme of research in developmental psychology. Theories of socialization view parent-child relationship as a family environment which has a significant and profound effect on child development. Since 1990s, studies from qualitative behavior genetics adopting the twin-study design have demonstrated that family environment including parent-child relationship has both genetic and environmental underpinnings. With the advancement of molecular genetics in the last decade, investigations about the gene-environment interactions yielded meaningful findings that significantly updated and deepened the scientific understanding of the nature of parent-child relationship. However, existing research on gene-environment interplay in parent-child relationship has mainly focused on the role of 5-HTTLPR and DRD4 gene polymorphisms, the possible association between COMT gene rs6267 polymorphism and parent-child relationship remains to be examined. Besides, most of previously reported findings were obtained on mother-infant attachment. It remains to be seen whether parent-adolescent relationships also have significant genetic underpinning, and whether there are moderating effects of gender and parenting behavior, including positive and negative parenting behavior on the association between rs6267 polymorphism and parent-adolescent relationship. The present study aimed to extend the previous research by examining the association between rs6267 polymorphism and parent-adolescent relationship, with particular focus on the moderating effect of gender and parenting behavior. The subjects of this study were 208 grade 7-9 adolescents (male = 106, female = 102). DNA was extracted from saliva, and genotype at rs6267 was performed for each participant in real time with MassARRAY RT software version 3.0.0.4 and analyzed using the MassARRAY Typer software version 3.4 (Sequenom). Data analysis was performed using the Statistical Package for Social Sciences 18.0 (SPSS 18.0). A series of hierarchical regression analyses were conducted to examine the interaction of rs6267 polymorphism with gender and with parenting behavior on parent-adolescent relationships. The findings showed that there was no main effect of rs6267 polymorphism on parent-adolescent relationship, but the interactions between rs6267 polymorphism and gender on parent-adolescent cohesion and mother-adolescent conflict reached significant, such that male adolescents with GG genotype possessing lower levels of cohesion with their parents and higher levels of conflicts with their mothers, while female adolescents with GG genotype reporting higher levels of cohesion with their parents and lower levels of conflicts with their mothers. There was only a marginally significant interaction between rs6267 polymorphism and maternal negative parenting behavior on mother-adolescent conflict. These above mentioned results will remain to be verified due to the limited sample size of the present study.

Key words: parent-adolescent conflict, parent-adolescent cohesion, COMT gene rs6267 polymorphism, parenting behavior, gene-environment interaction