The Etiologic Role of Genetic and Environmental Factors in Criminal Behavior

KS Kendler et al., PubMed, December 23, 2014



Twin studies have shown that criminal behavior (CB) is influenced by both genetic and shared environmental factors. Could these results be replicated using full-siblings and half-siblings?


In 911 009 full-siblings reared together (FSRT), 41 872 half-siblings reared together (HSRT) and 52 590 half-siblings reared apart (HSRA), CB was assessed from the Swedish Crime Register. Modeling, including testing for age differences and rearing status, was performed using the OpenMx package.


Five sibling models were fitted examining FSRT and HSRT 0-2 years different in age, and both FSRT and HSRT, and FSRT, HSRT and HSRA 0-10 years different in age with and without a specified shared environment indexing age differences. Heritability estimates for CB ranged from 33 to 55% in females and 39 to 56% in males, similar to those found in our prior twin study on the same population. Estimates for the shared environment varied from 1 to 14% in females and 10 to 23% in males, lower than those estimated in the twin study. The specified shared environment indexed by sibling age differences was significant in all models tested.


Heritability estimates for CB from full- and half-siblings closely approximated those found from twins in the same population, validating the twin method. Shared environmental estimates were lower, suggesting the presence of shared environmental factors for CB specific to twins. When rearing status can be assessed, full- and half-siblings offer an additional method for assessing the role of genetic and environmental factors in complex disorders. However, age differences in siblings may need to be included in the models.

Topics: ,

Share This

We welcome comments that add information or perspective, and we encourage polite debate. If you log in with a social media account, your comment should appear immediately. If you prefer to remain anonymous, you may comment as a guest, using a name and an e-mail address of convenience. Your comment will be moderated.
  • dd121

    We’ve been saying this for years. Hurrah, now we have science behind us!

  • superlloyd

    I would love to see the heritability estimates between blacks and whites.

    • Luca

      I understand that American prisons are fertile grounds for black, father-son reunions. And of course for most, it’s actually a first time meeting.

  • Luca

    My rule of thumb in all discussions like this is: 75% DNA – 25% environmental.

  • JohnEngelman

    In the fairly near future genes will be discovered that reliably predict IQ’s and crime rates of fetuses.

    • Luca

      They have that already John, it’s called a melanin test.

      • JohnEngelman


  • Bartek

    I’d like to see the study on passivity and the willingness to engage in self-hatred and support social and political causes that lead to self destruction.

  • LHathaway

    Paging John Engelman. I bet he’ll have something more interesting to say than this study.

  • IstvanIN

    Where do most black men first meet their sons? Prison.

  • Reynardine

    There actually is a very interesting portion of the Codex Theodosius, the body of Byzantine legal text circa the sixth century AD. It called for executing the FAMILIES of men found guilty of conspiracy to commit gang-related activities.

    The Romans are right again… it runs in the family…

    • Who Me?

      Actually you can find it even earlier–in the Bible. In the Old Testament God himself ordered the deaths of criminals guilty of certain crimes along with their entire families–wives, children and suckling babes.
      If you subscribe to the Christian belief that God created us, and that He is all-knowing, he surely knows how we are made and how DNA works to pass along all sorts of traits, from eye color to a tendency towards criminal behavior.

  • KevinPhillipsBong

    Hooray! More facts for them to ignore.

  • Fr. John+

    Sadly, this was a Swedish study, that most likely only observed Caucasoids, who have a clearly lower figure as a race for vehement crime. Only when they compile a study that concentrated on Blacks, and their disproportionate penchant for crime, will we get a truer picture why they should all be shipped back to Africa, to ‘add diversity’ to their ancestral homelands, and not foisted on the White American Natives.

  • guest

    H. J. Eysenck’s book CRIME AND PERSONALITY was taken back to the drawing board by him when research required reformulation. But for years and years, his work in this field of genes and propensity for criminal behavior was ignored in the US. He noted that among canines, the Basenjis had a very high incidence of “psychopathic” predisposition., I somehow doubt that in any American setting there has been over the last quarter of a century an effort to selectively breed “nice” Basenjis and “naughty” Basenjis. American are far more likely to face realism about the biological bases of dog differences than about human differences within the US. It is good to keep in mind that once human differences are indicated, a lot remains to be known as to specifically what it is that progressively uncorks propensity toward crime into actual criminal conduct. That sort of insight can allow most people so inclined to find cognitive-behavioral techniques to counter the tendencies.

  • ***