May 20, 2009 — Genes trump environment as
the primary reason that some adolescents are more likely than others to
be victimized by crime, according to groundbreaking research led by
distinguished criminologist Kevin M. Beaver of The Florida State
The study is believed to be the first to probe the genetic basis of victimization.
"Victimization can appear to be a purely environmental phenomenon,
in which people are randomly victimized for reasons that have nothing
to do with their genes," said Beaver, an assistant professor in FSU’s
nationally top-10-ranked College of Criminology and Criminal Justice.
"However, because we know that genetically influenced traits such as
low self control affect delinquent behavior, and delinquents,
particularly violent ones, tend to associate with antisocial peers, I
had reasons to suspect that genetic factors could influence the odds of
someone becoming a victim of crime, and these formed the basis of our
Beaver analyzed a sample of identical and same-sex fraternal twins
drawn from a large, nationally representative sample of male and female
adolescents interviewed in 1994 and 1995 for the National Longitudinal
Study of Adolescent Health. "Add Health" interviewers had gathered data
on participants that included details on family life, social life,
romantic relationships, extracurricular activities, drug and alcohol
use, and personal victimization.
The data convinced Beaver that genetic factors explained a
surprisingly significant 40 to 45 percent of the variance in adolescent
victimization among the twins, while non-shared environments (those
environments that are not the same between siblings) explained the
remaining variance. But among adolescents who were victimized
repeatedly, the effect of genetic factors accounted for a whopping 64
percent of the variance.
"It stands to reason that, if genetics are part of the reason why
some young people are victimized in the first place, and genetics don’t
change, there’s a good chance these individuals will experience repeat
victimization," Beaver said.
"It is possible that we detected this genetic effect on
victimization because it is operating indirectly through behaviors,"
Beaver said. "The same genetic factors that promote antisocial behavior
may also promote victimization, because adolescents who engage in acts
of delinquency tend to have delinquent peers who are more likely to
victimize them. In turn, these victims are more likely to be repeatedly
victimized, and to victimize others."
Thus, write Beaver and his colleagues, victims of crime are not
always innocent bystanders targeted at random, but instead, sometimes
actively participate in the construction of their victimization
"However, we’re not suggesting that victimization occurs because a
gene is saying ‘Okay, go get victimized,’ or solely because of genetic
factors," Beaver said. "All traits and behaviors result from a
combination of genes and both shared and non-shared environmental
And environmental factors can make a difference, he noted. The
social and family environment in an adolescent’s life may either
exacerbate or blunt genetic effects — a phenomenon known in the field
of behavioral genetics as a "gene X environment interaction."
Co-authors are criminology graduate students Brian Boutwell and J.C.
Barnes of Florida State and Jonathon A. Cooper of Arizona State