Violence is in the gene, after all. Yes, men who join gangs, are among the most violent members, and use weapons may be the carriers of a particular variation of the so-called "warrior gene," according to a study.
Conducted by Florida State University researchers, this is the first study to confirm a link between the warrior gene, scientifically known as Monoamine oxidase A (MAOA), and gangs and guns.
The researchers behind the study say that their findings apply only to men, as girls with the same variant of the MAOA gene seem resistant to its potentially violent effects on gang membership and weapon use.
Research leader Kevin M. Beaver, a noted biosocial criminologist at FSU's College of Criminology and Criminal Justice, says that this study sheds new light on the interplay of genetics and environment that produces some of society's most serious violent offenders.
"While gangs typically have been regarded as a sociological phenomenon, our investigation shows that variants of a specific MAOA gene, known as a 'low-activity 3-repeat allele,' play a significant role," said Beaver, an award-winning researcher who has co-authored more than 50 published papers on the biosocial underpinnings of criminal behaviour.
"Previous research has linked low-activity MAOA variants to a wide range of antisocial, even violent, behaviour, but our study confirms that these variants can predict gang membership. Moreover, we found that variants of this gene could distinguish gang members who were markedly more likely to behave violently and use weapons from members who were less likely to do either," he said.
The researcher points out that the MAOA gene affects levels of the neurotransmitters dopamine and serotonin, which are related to mood and behaviour, and those variants that are related to violence are hereditary.
The "warrior gene" has been found, in previous studies, to be more prevalent in cultures that are typified by warfare and aggression.
"What's interesting about the MAOA gene is its location on the X-chromosome," Beaver said.
"As a result, males, who have one X-chromosome and one Y-chromosome, possess only one copy of this gene, while females, who have two X-chromosomes, carry two. Thus, if a male has an allele (variant) for the MAOA gene that is linked to violence, there isn't another copy to counteract it. Females, in contrast, have two copies, so even if they have one risk allele, they have another that could compensate for it. That's why most MAOA research has focused on males, and probably why the MAOA effect has, for the most part, only been detected in males," he added.
For their research, Beaver and his colleagues examined DNA data and lifestyle information drawn from more than 2,500 respondents to the National Longitudinal Study of Adolescent Health.
Their findings have been published in the online edition of the journal Comprehensive Psychiatry. (ANI)