The Interaction Between Socioeconomic Status, Parent–Child Relationship, and the COMT Val158Met Polymorphism Predicts Chinese Preschoolers' Executive Function

The present study investigated the interaction effects of family socioeconomic status (SES), parent–child relationship, and COMT Val158Met polymorphism on the executive function (EF) of Chinese preschool-aged children. The sample comprised 748 preschoolers (M_age = 5.02 years, SD = 0.91, 50.1% boys) and their parents. Parents were asked to fill out several questionnaires assessing family SES, parent–child relationship, and their children's EF. Saliva samples were taken from the children for DNA analysis. Our analysis revealed a significant three-way interaction involving the crucial environmental factor, family SES, and the parent–child relationship, in conjunction with the individual factor, the COMT Val158Met polymorphism, in predicting the EF of preschoolers. The interaction between family SES and parent–child relationship was significant only for children with Val/Val genotypes. In contrast, this interaction was not significant for children carrying the Met/Met or Val/Met genotypes. The results of the present study highlight the complex interplay of multiple factors, including both distal and proximal family environments and individual genetic influences, that affect children's EF. These findings provide new insights into the multifaceted determinants of children's cognitive development.