Genetic Influence on Criminal Behavior Is Back on Criminologists’ Agenda

Experts are discussing how genes may influence criminal behavior at a meeting this week sponsored by the National Institute of Justice.

Just 20 years ago, a conference on genetics and crime sponsored by the National Institutes of Health was canceled after complaints that the research amounted to stereotyping and racism, the New York Times reports. The issue is back on the agenda now that at least 100 studies have shown genes can play a role.

Scientists caution that genetics are just one part of the puzzle and that a person’s environment has a strong influence, the story says. Nor is there just one crime gene. Instead, some genetic differences are linked to aggression and antisocial behaviors, which can increase the risk of crime.

One example: People with a version of a gene that results in less serotonin in the brain tend to be more impulsive and aggressive, but the effect of the gene is triggered by stressful experiences. Another example: A study of twins and siblings assessed the impact of environmental influences such as having delinquent friends or living in a disadvantaged neighborhood. In boys with none of the risky influences, genetics did not play any role in violent behavior. In those who experienced at least eight risk factors, genes explained 80 percent of their violence.

According to the Times, “The subject still raises thorny ethical and policy questions. Should a genetic predisposition influence sentencing? Could genetic tests be used to tailor rehabilitation programs to individual criminals? Should adults or children with a biological marker for violence be identified?”