Objectives：Impulsive aggression plays a critical role in the manifestation of violent and criminal behavior in adolescents and it also is a complex behavioral phenotype. The understanding brain mechanisms underlying impulsive aggression and identification of genetic risk factors is important to the prevention and treatment of impulsive aggression. Dopaminergic system plays an active role in the modulation of aggressive behaviors and hyperactivity in the dopamine system is associated with increases in impulsive aggression. We investigated the association of the impulsive aggression in Korean adolescent prisoners with DAT1 3'-untranslated region(UTR) variable number of tandem repeat(VNTR) polymorphism.

Methods：We recruited 198 male adolescent prisoner volunteers and 68 healthy controls and investigated the dopamine transport gene(DAT1) polymorphisms. Impulsive symptoms were measured using Barratt Impulsiveness Scale (BIS) and Achenbach's Child Behavior Checklist(CBCL). We divided all subjects into three groups by BIS, and then we compared genetic frequency and allele frequency between each subgroup.

Results：The distribution of the genotype in adolescent prisoners with 7/7, 9/10, 10/10, 10/11 were 7(3.8%), 12 (6.6%), 158(86.3%), 6(3.3%) and the controls were 2(3.2%), 5(8.1%), 52(83.9%), 3(4.8%), respectively. No significant differences for genotype distribution were revealed between adolescent prisoners and normal controls. Also there was no significant difference of genotype distribution between subgroups.

Conclusions：We failed to reveal the association between DAT1 polymorphism and impulsive aggression. In the future, larger sample size studies should continue to invest effort toward identifying the biological and genetic risk factors underlying impulsive aggression for developing effective treatment strategies.