Study On The Social Factors And Genetic Susceptibility Of The Male Adolescent Violent Crime

Part 1.Study on the social factors of the male adolescent violent crimeObjective:To explore the social influencing factors of adolescent violent crime.Methods:We selected male juvenile offenders(under the age of 25 years)from the youth correctional facilities of Hubei province as study objects by using cluster sampling method and defined them as case group.We handed out 1090 investigating questionnaires,and collected 1006 valid questionnaires(excluding the ethnic minority cases).Then we recruited 1300 volunteers(1182 valid questionnaires were obtained)from universities,high schools and junior high schools in Hubei province as control group.The control group matched case group in terms of age,gender,place of origin,and ethnicity.We compared the difference between two groups in environmental factors or psychological characters by using t test or chi-square test and construct the risk prediction model of male adolescent violence crime with multivariate logistic regression.Results:There were statistically significant differences(P<0.01)between case and control group about home environment(family type,educational mode and the feelings between parents),socioeconomic status(guardians' educational situation and income level),psychological characteristics(aggressive behaviors,trait anger and antisocial personality),childhood neglect and abuse,and violence exposure.The risk of male adolescent violent crime was significantly enhanced with the increasing of most influencing factors(exclude the frequency of network usage)with negative environment and the level of negative personality traits.Eleven factors,including emotional neglect,sex abuse,violence exposure,trait anger,companion's bad behavior or criminal behavior,taking drugs,antisocial personality disorder,smoking,guardian's educational situation and the family type,have a better predictive effect on male juvenile violent.Conclusion:Compared with the control group,the adolescent violent offenders have more negative environmental factors,more negative traits and bad behaviors.Emotional neglect,sex abuse,violence exposure,trait anger,companion's bad behavior or criminal behavior,taking drugs,antisocial personality disorder,smoking,guardian's educational situation and the family type are powerful predictors of male adolescent violent crime.Part 2.Relationship between DRD3?DRD4 and FEV genes polymorphism and genetic susceptibility of the male adolescent violence crimeObjective:To explore the genetic predisposition of the male adolescent violence crime by investigating the relationship between the male adolescent violence crime and DRD3,DRD4,and FEV gene polymorphism.Methods:We chose candidate genes located in the dopaminergic and serotonin system(DRD3,DRD4,and FEV)that had been previously reported to be associated with aggressive behavior.We analyzed 14 tag single-nucleotide polymorphisms(SNPs)in 318 cases and 558 controls using a SNPscan genotype.Multi-analytic strategy including logistic regression(LR),classification and regression tree(CART)was explored to analyze higher-order interactions between these SNPs and aggressive behavior.Results:Both logistic and CART analysis suggested that the rsl6859448 "G" to "T"mutation genotype significantly increased the risk of adolescent violent crime(OR=1.79,95CI%:1.32-2.43,Padjust<0.01).DRD4 haplotype rs11246226C-rs11246228T significantly reduced the risk of youth adolescent violent crime(OR=0.77,95%CI:0.52-0.96,P=0.02).In CART analysis,individuals carrying the combined genotypes of rs16859448TT/GT-rs11246228CT/TT-rs3773679TT had the highest risk(OR=5.25,95%CI:2.53-10.86)of note 8.Cumulative effect analysis show that with 9-10 number risk alleles at highest risk of violence crime risk(OR=7.20,95%CI:1.45 35.73,P=0.016).Although with 3-4 number risk alleles is only marginal statistical significance(OR=3.18,95%CI:0.85-17.05,P=0.08),but in general,with the increase of risk allele number,the greater the risk of violence crime,the trend test also statistically significant(P<0.001).Conclusion:rs 16859448 "G" to "T" mutation significantly increased the risk of adolescent violent crime.While the haplotype rs11246226C-rs11246228T significantly reduced the risk of youth adolescent violent crime.The risk of aggressive behavior in Chinese adolescents was highly associated with single and multiple-risk variants in DRD3,DRD4,and FEV and the risk of violence crime was significantly enhanced with increasing of risk allele number.Part 3.A preliminary investigation of interactions between DRD3 and FEV geneticvariants and environmental factors in male adolescent violent crimeObjective:To investigate the gene-environment interactions between DRD3 and FEV genetic variants and environmental factors in the male adolescent violent crime based on the first two parts.Methods:Multivariate logistic regression analysis was used to explore the interactions between DRD3-rs2134655,FEV-rs 16859448 and DRD3-rs3773679 and environmental factors in the male adolescent violence crime.Results:Before FDR adjustment,both emotional abuse and residential atmosphere were statistically related to rs213465(P=0.03)and physical abuse and sex abuse were statistically related to rs16859448(P=0.002;P=0.05).However,significant interaction was found only between rs 16859448 and physical abuse(P=0.03),and no significant interaction was found between emotional abuse or residential atmosphere and rs213465(P>0.05)after FDR adjustment.Under low level of physical abuse cases,the genotype has no effect on adolescent violence crime,but in high degree of physical abuse cases,GT or TT genotype could markedly increase the risk of adolescent violence crime(Y=0.28+0.1*X VS Y=0.43+0.35*X).In another word,rs16859448 genotypes could moderate the relationship between physical abuse and the male adolescent violent crime.Conclusion:After FDR adjustment,rs16859448 genotypes were statistically associated with physical abuse.rs16859448 genotypes could moderate the impact of physical abuse on male adolescent violent crime and this modulation is consistent with diathesis-stress model.