Study On Association Of 5-HTTLPR With Behavioral Problems In School-age Twins

To analyze the genetic and environmental influence on children’s psychological and behavioral problems, especially the association of 5-HTTLPR with children’s psychological and behavioral problems, and the gene-environment interactions on those problems,147 pairs of school-age twins were enrolled. The psychological and behavioral problems were assessed with the Achenbach Child Behavior Checklist (CBCL). Family cohesion questionnaire (FACES Ⅱ-CV) and family general condition questionnaire were used to investigate the influences of environmental factors. Structural equation modeling was performed to evaluate the heritability of psychological and behavioral problems in school-age children. Using generalized estimating equation to evaluate the association of 5-HTTLPR and children’s psychological behavioral problems.The results were as follows:(1) The overall incidence rate of psychological and behavioral problems in school-age twins is 24.15%, and in boys and girls are 27.94% and 20.89% respectively. (2) For overall incidence rate of psychological behavioral problems, the heritability is 25.53%. Adjusting for age, the heritabilities in the twin boys for withdrawn, attention, social problems, rule-breaking, aggressive and externalizing are higher (59.08%～85.45%), but for anxious/depressed, total variable and internalizing are lower (27.57%～42.75%). In girls, the heritabilities for anxiety/depression and withdrawn are higher (64.32%～85.19%) but for the attention problems, social problems, aggressive, total variable and internalizing are lower (13.42%～45.56%). There is some gender difference in the heritability of each psychological and behavioral problem. (3) Child gender, monozygotic/dizygotic, parental child-bearing age, father educational level, parental occupation, family environment and rearing patterns are the influence factors of psychological and behavioral problems. (4) 5-HTTLPR S allele may be associated with anxious/depressed and social problems. The interaction of 5-HTTLPR with monozygotic/dizygotic affect aggressive. Moreover, the interaction of 5-HTTLPR with family environment and family rearing patterns affect anxious/depressed respectively.In conclusion, the psychological and behavioral problems of school-age children are influenced by genetic and environmental factors. 5-HTTLPR may be associated with anxious/depressed and social problems. Family environment and family rearing patterns are the major environmental factors of psychological and behavioral problems. The results of this study are significant in promoting and improving children’s physical and mental health in Inner Mongolia, combined with children’s genetic background, also provide basis for educators and parents to conduct effective intervention on children’s mental, behavioral, nutrition and health status.