OBJECTIVETo study the effects of rs4274224 polymorphisms in the DRD2 gene, family factors and their interaction on the regularity in school-age children.

METHODSThe rs4274224 polymorphisms were genotyped using Sequenom Mass Array. The regularity was assessed based on the Middle Childhood Temperament Questionnaire (MCTQ). The parental rearing pattern was assessed with Egna Minnen av Bardnodnauppforstran (EMBU). The family function was assessed using Family Cohesion and Adaptability Scale (FACES II-CV).

RESULTSThe regularity score in children with AA genotype of rs4274224 in the DRD2 gene was significantly lower than in those with GA/GG genotype (2.9±0.6 vs 3.1±0.7; P<0.05). The results of multiple regression analysis showed that the regularity was related to child gender, father's education level and family adaptability. The results of logistic regression analysis showed that the main factors influencing the regularity were family adaptability and its interaction with rs4274224 polymorphisms. The regularity was better in children with high family adaptability than in those with low family adaptability (OR=0.112, P<0.01). The children with AA genotype and low family adaptability were tend to be associated with low regularity (OR=21.554, P<0.01).

CONCLUSIONSThe regularity based the temperament for school-age children might be influenced by family adaptability and its interaction with rs4274224 polymorphisms.