Genetic background of extreme violent behavior.

Area of Science:

• Genetics
• Criminology
• Neuroscience

Background:

• Violent crime is often committed by a small group of offenders.
• No specific genes have been identified for violent offending or severe violent behavior like homicide.

Purpose of the Study:

• To investigate the genetic underpinnings of extreme violent behavior.
• To identify specific genes associated with recidivistic violent offending.

Main Methods:

• Analysis of two independent cohorts of Finnish prisoners.
• Genotyping for monoamine oxidase A (MAOA) low-activity genotype and the CDH13 gene.

Main Results:

• A low-activity MAOA genotype and the CDH13 gene were associated with extremely violent behavior (≥10 offenses).
• These genetic associations were specific to violent offending, not linked to substance abuse or antisocial personality disorder.
• MAOA and CDH13 genotypes may account for 5-10% of severe violent crime in Finland.

Conclusions:

• Low monoamine metabolism and neuronal membrane dysfunction are potential etiological factors in extreme criminal violence.
• Specific genetic profiles (MAOA and CDH13) are implicated in severe violent offending.
• Genetic predispositions may contribute significantly to the prevalence of violent crime.