The Relevance Of DRD4 Exon â…¢ VNTR Polymorphism, Psychology, Living Environment Of Violent Offenders In Chongqing

A violent crime or crime of violence is a crime in which the offender uses or threatens to use violent force upon the victim. It is more harmful to society than other crimes although its rate is low. And, prevention violent crime is the focus work in public security. Some studies have reported that DRD4 was one of Dopamine receptors in brain of mammals, regulated various pathophysiology functions. It was involved in schizophrenia, Parkinson's disease, drug abuse, and so on. Recently, accumulating evidences indicated that DA were associated with drug abuse and consciousness stress, and, promoted study which association between DA and assaultive behavior. At the same time, some studies have showed that DRD4 gene VNTR polymorphisms may be strongly linked to affective disorders. Also it is verified that the VNTR(L) type of this gene is related to the activity of DRD4 receptor.In our study, we investigated whether exonâ…¢48bp VNTR in DRD4 gene polymorphism are associated with violent crime in Chongqing Chinese population using polymerase chain reaction (PCR), including 622 unrelated healthy individuals who served as controls and 621 unrelated violent crimes who served as experimentals. To reveal relation of environmental factors, psychological factor, and genetics, we also analyzed individual home environment, educational background, and employment by rough set data mining, and studied the association of nerval and psychical factors, DRD4 VNTR polymorphism, and violent crime using Eysenck Personality Questionaire (EPQ).The results were showed:1. The 48bp VNTR genotype distributions in our control and experimental subjects agreed with that expected under Hardy-Weinberg equilibrium (P>0.05). The most abundant allele was the 4-repeat allele, followed by the 2-repeat allele. The most repeats were 7, not 8 repeats allel. Individuals have been grouped as either "short" carriers or "long" carriers with the category of "short" (S-VNTR) being defined as 5 or fewer repeats and "long" (L-VNTR) as 6 or more repeats. We failed to find any significant difference in the control and experimental groups according to S-VNTR and L-VNTR, respectively. But the distribution frequency of the long allele(L-VNTR) in the population of crime is larger than normal proportion of large crowd. 2. Crime of theft and robbery were mainly in teenagers with illiterate/ elementary school level and no good family economy by background investigation. These subjects did not satisfactory education and knowledge.3. Psychological investigation showed that the strong association between various kinds'crimes and abnormality with nerves and psychology. It might be possibility guilty of robbery, murder, extortion, rape or intentional injury in high psychoticism dimension.4. Individuals with DRD4 4-repeat carriers, less than moderately livelihood and middle school level, excessive nervousness, and abnormality psychoticism were easy to occurred violent criminal predisposition. The correlation of the DRD4 gene exon III genotype 4/4 and the type of criminal homicide and robbery of crime 18-30 years old is a little high.