Researchers link genes to criminal tendencies

RALEIGH, N.C. – Maybe some boys really were born to be wild.

Researchers at UNC Chapel Hill announced this week that they had found three genes that appear to affect the probability of a life of crime.

The study looked at roughly 1,100 boys ages 12-18.

In 1996 and again in 2002, the participants were asked to take a 12-question survey to gauge their delinquent tendencies. The participants’ delinquency scores were matched against their genetics to look for a correlation.

The results clearly showed a genetic basis for aggressive behavior.

The idea that personality and behavior can be predicted by genetics is not a new one, and it has a dark past. “Bad genes” were the basis in the 19th century for Henry Goddard’s theory of eugenics, which was used as a justification for racial supremacy.

In the current research, scientists emphasized that having the gene doesn’t necessarily mean a child is destined to become a criminal.

“It’s not like with some genetic diseases, like cystic fibrosis or Huntington’s, where when you have the genes the likelihood increases by 5,000 fold,” said Guang Guo, a professor of sociology at UNC-CH and the study’s lead author. “If you have the genotype you’re not necessarily going to be a delinquent.”

Parenting and other social factors can completely override the influence of the genes, he said.

From an evolutionary perspective, aggressive behavior might be beneficial. According to the UNC-CH team’s research, which will be published in the August edition of American Sociological Review, boys who tend to be more aggressive could have advantages when it comes to getting a mate, protecting their families and getting enough food.

Studies of violent behavior among wild chimpanzees suggested to the study’s authors that “human violence is rooted in pre-human history.”