Objective To explore the influence of genetic and environmental factors on adolescents depressive symptoms. Methods The depressive mood were investigated in 107 twin pairs from Chongqing (aged from 11 to 18 years old) using Beck Depression Inventory (BDI). The Parenting Styles and Dimensions Questionaire (PSDQ), Family Stresses Questionnaire (FSQ), Family Adaptability and Cohesion Scale 2nd Edition Chinese Version (FACES II-CV) and Stressful Life Event (SLE) were applied to assess their environment factors. The blood samples were collected to identify zygosity of twins. Structural equation model was performed to evaluate the effects of the additive genetic factors (A), shared envi?ronment factors (C) and individual specific environmental factors (E) on the adolescents depressive mood. Results The scores of depressive mood were negatively correlated with father’s education level (r=-0.15, P=0.03), mother’s educa?tion level (r=-0.17, P=0.01), scores of the authoritative-parenting-style (r=-0.18, P<0.01), scores of the family adaptabil? ity (r=-0.27, P<0.01) and family cohesion (r=-0.20, P<0.01). There were significantly positively correlation between de?pressive mood and family stresses scores (r=0.14, P=0.04). The scores of adolescents depressive mood were not signifi?cantly correlated with stress life events (P>0.05). The effects of A and E on adolescents depressive symptoms were 0.37 (95%CI:0.14~0.57) and 0.63 (95%CI:0.43~0.86), respectively. Conclusion The authoritative-parenting-style and fami?ly adaptability are negatively correlated with depressive mood. Family stresses are positively correlated with depressive mood. Adolescents depressive mood is influenced by genetic factors and, to a greater extent, specific environmental factors.

Objective Using twins methods to explore the influence of genetic and environmental factor on Intelligence develop-ment of children and adolescent twins .Methods It was 190 pair of twins aged 6 to 18 who lived in Chongqing were recruited ,DNA were extracted from buccal mucosa and venous blood samples to identify zygosity .The intelligence was investigated by using the Wechsler Intelligence Scale for Children(C-WISC) ,the intrapair correlation coefficients of twins were compared and calculate the genetic degrees .Results The total IQ of children aged 6 to 18 heritability were 0 .63 ,Verbal IQ were 0 .44 ,Performance IQ were 0 .57 .The total IQ heritability of children aged 10 to 14 and 15 to 18 years(0 .78 ,0 .79) were higher than that of those aged from 6 to 9 years(0 .018) .Conclusion This study suggested the intelligence of children aged 6 to 18 affected by genetic and environment , and the older ,the more influence of genetic on intelligence development .

Objective To explore the influence of genetic and environmental factors on emotional and behavioral problems in children and adolescents using twins quantitative method. Methods One hundred fifty-six twins pairs, aged from 6 to 18, were included in the present study. The parental version of the strengths and difficulties questionnaire (SDQ)was used to evaluate their emotional and behavioral problems. The DNA test of twin zygosity was conducted using DNA extracted from buccal mucosa or venous blood samples. The influence of genetic and environmental factors on emo-tional and behavioral problems was analyzed using structural equation modeling(SEM). Results Shared environment and special environment had impact on emotional symptoms and their contribution to the total variance of emotional symp- tom was 0.42 and 0.58, respectively. Prosocial behavior was mainly affected by shared environment and the contribution of shared environment to the total variance of prosocial behavior was 0.89. Genetic factors had greater influence on hyperac-tivity/attention deficit and the contribution of genetic factors to the total variance was 0.62. Shared environment had more influence on conduct disorder and the contribution of shared environment to total variance was 0.56. Heredity, shared envi-ronment and special environment had impact on peer problems and their contribution to the total variance was 0.24, 0.33 and 0.43, respectively. Conclusion In child and adolescent period, emotional symptoms are only affected by environ-ment, while behavior problems are affected by the combination of heredity and environment. Different behavior problems are affected by different genetic and environmental factors.

OBJECTIVETo explore the influence of genetic and environmental factors on the executive function of twin children.

METHODSThe executive function of 122 twin pairs from Chongqing (aged from 6 to 18 years) were investigated with the perseverative errors of the Wisconsin Card Sorting Test. Structural equation modeling was performed to evaluate the effects of the additive genetic factors (A), dominance genetic latent factors (D) and individual specific environmental factors (E) on the executive functions.

RESULTSThe effects of D and E on perseverative errors were 0. 77 (95%CI: 0.65-0.84) and 0.23 (95%CI: 0.16-0.35), respectively. The probability of perseverative errors showed a significant negative correlation with family functioning and with the total GHQ-12 scores of the fathers and mothers (r:-0.335, -0.335, and -0.219, respectively, P<0.01). Perseverative errors were not significantly correlated with the parenting styles and stress life events.

CONCLUSIONPerseverative errors are influenced by a common dominance genetic latent factor and individual specific environmental factors, but the role of environmental factors such as family functioning and parental health can not be ignored.

Adolescent ; Child ; Environment ; Executive Function ; Genotype ; Humans ; Neuropsychological Tests ; Phenotype