Study On The Effects Of Polygenes Of Dopamine Receptor System And Family Environmental Factors And Temperament On The Psychological Behavior Problems Of School-age Children

Psychological and behavioral problems in children are common during their growth,and abnormal behavior may lead to psychological problems in adulthood,which are influenced by multiple genetic and environmental factors.In order to understand the impact of dopamine receptor system genes,important family environmental factors and temperament on the psychological and behavioral problems of school-age children,this study randomly selected 450 Han children aged 8～12 years in Arhorqin Banner,Chifeng City,Inner Mongolia,and evaluated their psychological and behavioral problems with the Achenbach Child Behavior Scale;The Carey’s standardized temperament questionnaire（MCTQ）was used to assess children’s temperament;The TIANamp Swab DNA Kit was used to extract whole genome DNA;The PCR amplification technology was used to type the DRD2 gene Taq1A and DRD4 gene exon III 48bp VNTR;15 single nucleotide polymorphisms（SNP）genotypes of dopamine receptor gene were determined by i MLDR^TM technology;Theχ² test,independent sample t test,ANOVA analysis of variance were used to the single factor analysis,and the binary logistic regression,multiple linear regression,general linear model,and generalized estimation equation were used to the multivariate analysis;The Haploview 4.2 software was used to perform linkage disequilibrium testing on 15 SNPs;The Phase software was used to haplotype analysis;The PROCESS v4.0 software was used to test the mediating effect of temperament.The results showed that:（1）In the occurrence of psychological and behavioral problems in school-age children,the DRD4 gene exon III 48bp VNTR is associated with socialization problems,thinking problems,attention problems,introverted behavior,extraverted behavior,and overall behavior problems（p<0.05）,rs267418 is associated with disciplinary behavior（p<0.05）,rs6280 is associated with anxiety and depression,attention problems,and extraverted behavior problems（p<0.05）,rs1967551is associated with physical discomfort anxiety and depression were associated with overall behavioral problems（p<0.05）.The interaction between the DRD4 gene exon III 48bp VNTR 4R4R genotype and the CT and TT genotypes in rs6280 had an impact on outward sexual behavior（p<0.05）.The CA haplotype composed of rs3758653-rs936461 was associated with overall behavioral problems（p<0.05）;In the scores of psychological and behavioral problems in school-age children,the DRD2gene Taq1A was associated with socialization problems and disciplinary behavior（p<0.05）,rs6280 was associated with withdrawal behavior and introverted behavior（p<0.05）,rs3758653 was associated with disciplinary behavior（p<0.05）,rs1967551 was associated with introverted behavior（p<0.05）,and the CA haplotype composed of rs3758653-rs936461 was associated with attention problems,disciplinary behavior,extraverted behavior,and overall behavioral problems.（2）The main environmental factors affecting the psychological and behavioral problems of school-age children are gender,temperament,father’s occupation,whether there is a disease during pregnancy,whether there is a term birth,delivery mode,main caregivers,major events,family cohesion and adaptability,and parenting style（p<0.05）.（3）The interaction between CT genotype and negative temperament type in rs6280 has an impact on the occurrence of extraversion behavior in school-age children（p<0.05）.（4）The temperament dimension partially or completely mediates the impact of major events and delivery methods on children’s introverted behavior problems;The temperament dimension partially or completely mediates the impact of family intimacy and adaptability on children’s overall behavioral problems;The multiple dimensions of temperament partially or completely mediate the influence of parenting style on children’s introverted behavior,extroverted behavior and total behavior problems.The main conclusions of this study are as follows:（1）The DRD2 gene Taq1A,DRD4 gene exonⅢ48bp VNTR,rs267418,rs6280,rs3758653 and rs1967551 in the dopamine receptor system gene are related to some children’s psychological and behavioral problems.（2）The interaction between rs6280 and temperament types has a certain impact on children’s extraverted behavior.（3）Temperament has an obvious mesomeric effect in the influence of parenting style on children’s behavior problems,and there is also a certain mesomeric effect in the influence of family cohesion and adaptability,major events and delivery methods on children’s behavior problems.