My 'Warrior Gene' and My Propensity for Criminality

It's way too early to start putting people like me in jail based on our genomes


Abode of Chaos/Flickr

Researchers have been probing the human genome in search of genetic variants that might affect the propensity to violent and criminal behavior. Lots of studies have focused on versions of the monoamine oxidase A gene (MAOA). This gene produces an enzyme that controls the levels of various neurotransmitters such as dopamine and serotonin. I was intrigued by a recent study in which Finnish researchers report that low activity versions of MAOA are associated with violent criminal behavior and higher rates of recidivism. The researchers also found that interactions with versions of another gene CDH13 exacerbates criminal tendencies. In fact, the researchers calculated that "at least about 5-10% of all severe violent crime in Finland is attributable to the aforementioned MAOA and CDH13 genotypes."

The low and high activity versions of the MAOA gene are distinguished by a promoter region that can consist of repeats of a 30-base pair sequence that reduce or increase MAOA activity. Low activity results from having just 2 or 3 repeats, whereas high activity stems from 4 or 5 repeats of this sequence. The low activity version of MAOA has been nicknamed the "warrior" gene.

Some time back I deposited the raw results of my genotype screening tests from 23andMe at SNPedia where it is constantly updated by Promethease. I was curious to see what version of the MAOA gene I happen to have. It turns out that I very likely have the 3-repeat warrior variant. Hmm. My last fight was in 8th grade and I have so far avoided jail. The Finnish researchers also report that drinking alcohol heightens the risk that those affected with the low activity MAOA variants will behave violently. I do confess to occasionally raising my voice during arguments (usually over politics or architecture) fueled by alcohol, but none have ever come to fisticuffs.

So what about my CDH13 alleles? It turns out that I am homozygous for the protective version of that gene. So maybe that helps to explain my relatively placid nature.

Would widespread genotyping for these variants be useful; perhaps by applying some form of intervention to forestall violent acts by affected males? Medpage Today notes that Vanderbilt University forensic psychiatrist Stephen Montgomery thinks that "the relatively low population-attributable risk meant that there is no immediate practical application, since many individuals carrying the risk alleles identified in the study have no history of violence, and many violent individuals don't carry them." In other words, it's way too scientifically premature to start putting people like me in jail based on our genomes.

Go check out my Promethease results to see what else is wrong with me.

Via the invaluable Genetic Literacy Project.

NEXT: Sorry, It's Still Not 1968: DNC/RNC Protesters and Police Prove Dissent and Order can Coexist

Editor's Note: We invite comments and request that they be civil and on-topic. We do not moderate or assume any responsibility for comments, which are owned by the readers who post them. Comments do not represent the views of or Reason Foundation. We reserve the right to delete any comment for any reason at any time. Report abuses.

  1. The sad truth is that you’re left with only one option: Double Mastectomy.

  2. At what point would your genes justify precrime?

    1. If it saves just one life lock ’em up.

    2. Look, if putting Ron in jail potentially saves one child, I say we are obligated to do it!

      1. He’s a transhumanist libertarian. He’s all for letting rich folks tailor superbabies to enslave the poor.

        1. And that’s where we part ways.

          I’m a supporter of vat-grown orphans, rather than poor-enlsaving superbabies.

    3. They already do.

      Ron has a y Chromosome and therefore he is automatically a member of the patriarchy and at the very least a pre-rapist and should be locked behind bars for the protection of all proper humans (who are defined as only having X chromosomes)

      1. “Ron has a y Chromosome”

        citation needed

  3. NB4 the usual suspects make claims about racial correlations vis-a-vis warrior gene prevalance

    1. Damn, I had something for this…Zulus….never mind.

    2. Finns, obviously. Are they a race or do the Russians invade often enough to keep the gene pool well mixed with greater Eurasia?

  4. Researchers have been probing the human genome in search of genetic variants that might affect the propensity to violent and criminal behavior.

    I knew they were going to be on to us sooner rather than later. I just knew it!

  5. While interesting, it appears it’s way too early to use this information to help people predict if they are at risk of being inclined to anti-social or criminal behaviors.
    It reminds me of all the pharma meds that have various side-effects. We can’t seem to get it right. Many are very helpful, but I worry about how our benevolent overlords will use this…to “help us.”

    1. I’d say that the government may start dosing children with pacifying drugs, but that would be too paranoid.

      1. No need for drugs, they’ve perfected the Ludovico technique.

        1. Umm, those, “…vitamins…,” injections that Alex was administered are what caused him to become adversely sensitive towards and react violently inwardly to all the images to which he was exposed.

          Otherwise, +1 eye drops.

          1. That’s why I said perfected. He also shrugged off the conditioning at the end.

    2. And what exactly do you do once you identify people at risk of being inclined to anti-social or criminal behaviors?

      Oddly enough, I’m going to guess a large number of the people in uniformed positions in government probably have it. Cops and military.

  6. You say “too early” I say not too early enough!

  7. At least about 5-10%? Sounds concrete to me.

  8. “At least about 5-10%” doesn’t sound to me like any kind of correlation whatsoever.

    This must be the new “science”. You know, that same kind of new science where you predict temperature will go up several degrees, then when it doesn’t you claim you were right, but the planet stubbornly didn’t cooperate, and all that sort of crap.

    1. Its really frustrating to me when people use statistics in that way. There’s no fucking way they isolated all the other possible correlating factors.

  9. I’m not saying to throw these people in prison but do we really want them owning assault rifles?

  10. Hey look, bullshit pseudoscience.

    1. Yes. I hope that Bailey is kidding here when he says “yet”. There should never be a time when we put people in jail or even intervene, whatever that means, based on some projection that they might some day be violent.

    2. Exactly. I’d bet that of you measured their skulls, you’d find that the module for intelligence is smaller than average.

  11. “Your Honor, my client was born a criminal. See these genes here?”
    “I see them.”
    “You see, these genes compel my client to engage in criminal behavior. It’s just the way he was born.”

    Cue Lady Gaga’s anthem, maybe some rainbows as well

    1. “The stars never compel; they merely impel.”

  12. The third precog is voting Trump.

    1. But that’s not the future the other two saw! IT’S ALL A SHAM!

  13. Atheists / secular humanists scare me more than the Trumpkins.

    1. That’s a handy bit of information. Do you perhaps have a newsletter that I might subscribe to?

      1. Talk to me, Sparky. Your secrets are safe with me:

    2. BOO! Hope you didn’t fall off your perch!

      1. Don’t worry Ernie you could still be a good person even if your genes made you do it.

        1. I AM a good person!!!


  15. I can’t help but wonder if the same genes have other effects. To say it’s involved in criminal behavior is pretty much meaningless. Genes don’t know crime or non-crime. And I can’t help but suspect that the same behavioral elements that make it more closely associated with criminal behavior might well make it more closely associated with other behaviors, some of which may be entirely desirable.

  16. Just a thought: how ’bout checking the occurrence of this gene in noble prize winners (or other high achievers) as compared with the general population? Might be interesting….

  17. 1) The abstract said that at least 10 of the offenders studied committed homicide, attempted homicide or battery.

    That is quite the large sample size. How were they able to compile all that data in such a short time?

    2) A study which shows that 5-10% of all violent crime, IN FINLAND, may have been committed by those with these genotypes. How is the representative of the rest of Europe (or those of European heritage here), much less the world?

    3) Warrior gene???? I mean FFS?

  18. Put on your warrior jeans, Bailey.

    1. Somebody needs to come out and play-hey..

  19. Would widespread genotyping for these variants be useful; perhaps by applying some form of intervention to forestall violent acts by affected males?


    1. 0: The gene is on the X chromosome, so women are more liable to get a protective version to ameliorate the crime-prone version. Interestingly, there is a study that suggests that women who have two low activity MAOA gene are more likely to be happy than those with high activity versions.

Please to post comments

Comments are closed.