Twin Method To Explore The Heritability Of Cognitive Function Index In Children And Adolescents Evaluation Of Cognitive Function Endophenotypic

Objective：To explore more stable and precise endophenotype in index of cognitivefunction with twin method and provide the basis on etiology of mentalillness. To analyze environmental factors on cognitive function and provideguidance of early intervention for mental disease, promote the mental healthof children and adolescents.Methods：Twins who live together in chongqing, aged from6to18, wererecruited by Student Registration. The cognitive function of children, wereinvestigated with China Revised Wechsler Intelligence Scale for Children,Spatial Working Memory, Rapid Visual Information Processing and thePattern Recognition Memory of Cambridge Automated NeuropsychologicalTest. DNA were extracted from buccal mucosa or venous blood samples andzygosity was identified. The influence of genetic and environmental factor on cognitive function was analyzed with Structural Equation Modeling.Result：1190twins intelligence were tested in this study and167twinszygosity was identified (including88homozygotic twins and79dizygotictwins);65twins were investigated with Cambridge AutomatedNeuropsychological Test;65pairs in Spatial Working Memory and PatternRecognition Memory(including35homozygotic twins and30dizygotictwins), While53pairs zygosity was identified successfully in Rapid VisualInformation Processing(including29homozygotic twins and24dizygotictwins).2There were no statistical significance in year of the education,gender and age in homozygotic twin and dizygotic twin in intelligence testand the Cambridge Automated Neuropsychological Test (p>0.05).3In index of cognitive function, genetic factors contributed to totalintelligence quotient most, can be used as the more valuableendophenotype (heritability:0.76).4Genetic factors and special environment contribute to the totalvariance of the total intelligence quotient were0.76and0.24respectively.Heredity, shared environment and special environment had impact on verbalintelligence quotient, accounted for0.51,0.34and0.15in the total variancerespectively. Shared environment and special environment contribute to thetotal variance of performance intelligence quotient were0.73and0.27 respectively. Genetic factors and shared environment contribute to the totalvariance of the number of the Spatial Working Memory between errors were0.38and0.62respectively. Shared environment and special environmentcontribute to the total variance of the strategy of Spatial Working Memorywere0.36and0.64respectively. Shared environment and specialenvironment contribute to the total variance of Rapid Visual InformationProcessing were0.27and0.73respectively. Shared environment and specialenvironment contribute to the total variance of Pattern RecognitionMemory were0.15and0.85respectively.ConclusionTotal intelligence quotient can be used as the more stable and valuableendophenotype. Heredity, shared environment and special environmenthave impact on verbal intelligence quotient. The number of errors betweenthe spatial working memory groups is mainly affected by environment. Therest of the indicators is influenced by shared environment and specialenvironment, special environment play a main role in factors. Environmentfactors on the cognitive function of children should not be ignored.