Scientists have found evidence that a genetic risk for low educational attainment is associated with having a criminal record in adulthood. Their new study, published in Psychological Science, provides evidence that some genetic variants are loosely linked to criminal behaviors.
But the findings don’t mean some people are destined to a life of crime just because of their DNA.
“I am interested in finding out why some people become involved in crime and antisocial behavior whereas others do not,” explained Jasmin Wertz, a postdoctoral fellow at Duke University and corresponding author of the study.
“Previous work shows that both ‘nature’ and ‘nurture’ contribute to individual differences in antisocial behavior. In this study we wanted to take a closer look at genetic associations with crime, by testing whether a genetic signature previously discovered in a genome-wide association study of educational attainment can also predict criminal offending and if so, why.”
The previous research has allowed scientists to create a “polygenic score” for educational attainment, which summarizes the joint effects of specific genetic variants. Those with a lower score tend to complete fewer years of formal education.
Wertz and her colleagues examined data collected in two longitudinal studies from the United Kingdom and New Zealand: the E-Risk Longitudinal Twin Study and the Dunedin Multidisciplinary Health and Development Study.
They found that individuals with lower polygenic scores for educational attainment were slightly more likely to have a criminal record in adulthood. This association remained even after the researchers accounted for the effects of socioeconomic deprivation and parental antisocial behavior.
“I think there are three main takeaways: First, genetic discoveries for educational attainment are not related to education only. The same genetics also predict other important outcomes, such as criminal offending,” Wertz told PsyPost.
“Second, the effects of the genetic score on crime were small. The majority of people will never receive a criminal record, regardless of their polygenic score. It is not possible to accurately predict who will become a criminal based on our findings.
“Third, the genetic influences we examined became visible as behavioural difficulties already early in life,” Wertz said. “Thus, genetics shape behavioral risks for crime that are manifest well before differences in educational attainment crystallize. Helping children develop better cognitive and self-control skills and improving their school experiences may prevent genetic influences on crime from unfolding.”
Wertz and her colleagues also found that low cognitive ability, poor self-control, academic difficulties and truancy, connected differences partially mediated the association between the polygenic scores for educational attainment and criminal behavior. In other words, these factors connected differences in DNA with participants’ later criminal offending.
“Our understanding of why the education polygenic score is associated with crime (or any other outcome for that matter) is still very limited,” Wertz explained. “We found that poor cognitive and self-control skills explained part of the association, but the pathway from genes to behaviors is very long and we are yet to fully understand what happens in the bodies and brains of people with a low versus high polygenic score that might affect their behaviors.”
“Another interesting question follows from our finding that the polygenic score was associated with the criminogenic environments people grew up in. Although this did not explain away our findings, it is an interesting observation in itself because it blurs the separation of ‘nature’ and ‘nurture’. It will be interesting to study further how nature and nurture combine to influence people’s lives.”
Both genetic and environmental factors contribute to criminal behavior.
“Some people mistakenly think that genetic influences on antisocial behavior imply that some people are born criminals. However, this interpretation is incorrect for several reasons,” Wertz said.
“First, although we found that having a low polygenic score for educational attainment increased the risk of engaging in crime, even among individuals with very low scores the majority had no criminal record.”
“Second, environments are at least as important as genetic influences in explaining why some people behave more antisocially than others and, third, genetic risk operated through behaviors and characteristic that can provide targets for intervention, such as low self-control and academic difficulties,” Wertz concluded.
The study, “Genetics and Crime: Integrating New Genomic Discoveries Into Psychological Research About Antisocial Behavior“, was authored by J. Wertz, A. Caspi, D. W. Belsky, A. L. Beckley, L. Arseneault, J. C. Barnes, D. L. Corcoran, S. Hogan, R. M. Houts, N. Morgan, C. L. Odgers, J. A. Prinz, K. Sugden, B. S. Williams, R. Poulton, and T. E. Moffitt.