Phenotypic Structure and Genetic Architecture of Personality 65antisocial personality diagnosis, Eysenck’s Psychoticism, and
Zuckerman’s Impulsive–Sensation Seeking. The third factor,
labeled Inhibition, was defined by intimacy problems and re-
stricted expression of inner experiences and feelings. The
factor correlated negatively with NEO-PI-R and EPQ Extra-
version and resembled theDSM-IVavoidant and schizoid
personality disorders. The fourth factor, Compulsivity clearly
resembled NEO-PI-R Conscientiousness and DSM-IV
obsessive-compulsive personality disorder. The loadings de-
rived from the phenotypic correlation matrices were remark-
ably similar: Congruence coefficients ranged from .94 to .99.
The congruency coefficients between the genetic and pheno-
typic factors on Emotional Dysregulation, Dissocial, Inhibi-
tion, and Compulsivity were .97, .97, .98, and .95, respectively.
The congruence between factors extracted from the pheno-
typic and nonshared environmental matrices were also high at
.99, .96, .99, and .96, respectively. These data suggest that the
phenotypic structure of personality and personality disorder
traits closely reflects the underlying etiological architecture.
This conclusion is also supported by a study of the pheno-
typic structure and genetic architecture of the five-factor
model assessed using the NEO-PI-R in two independent
samples of twins recruited in Germany and Canada (Jang,
Livesley, Angleitner, Riemann, & Vernon, in press). Factor
analysis of the genetic and nonshared environmental covari-
ance matrices yielded five factors that strongly resembled N,
E, O, A, and C (Neurotic, Extraversion Openness, Agreeable-
ness, and Conscientiousness). Congruence coefficients
computed between the genetic factors and the published
normative structure were .83, .72, .92, .88, and .70 for N, E,
O, A, and C, respectively. The congruence of the nonshared
environmental factors and normative structure was even
higher at .96, .93, .90, .93, and .97 for N, E, O, A, and C,
respectively.
The interesting feature of these results is not only that phe-
notypic structure resembles genetic structure, but also that the
structure of environmental effects is similar to the genetic
structure. Plomin, DeFries, and McClearn (1990) noted that
across a range of studies, “the structure of genetic influences
seems to be similar to the structure of [nonshared] environ-
mental influences” (p. 236). They added that this is surprising:
“Most of us would probably predict different patterns of ge-
netic and environmental influences” (p. 236). Recently, how-
ever, it has been suggested that genetic factors are more
important than are environmental influences in shaping trait
structure because the resemblance of the structure of non-
shared environmental effects to the observed structure of
traits may be artifactual (McCrae, Jang, Livesley, Riemann, &
Angleitner, in press).
Nonshared environmental effects are usually estimated
as a residual term that may include systematic bias such as
that introduced by implicit personality theory. Passini and
Norman (1966) demonstrated this bias by asking students to
rate the personalities of complete strangers. Although each
rating was presumably a guess, a clear pattern to the ratings
was found. Students who assumed that strangers were talka-
tive also assumed that they were sociable and cheerful. Across
a range of targets, these associations defined an ExtraversionTABLE 3.2 Rotated Principal Component Factor Loadings of Additive Genetic and Nonshared
Environmental Correlations
Genetic Factors Environmental Factors
Dimension 1 2341234
Submissiveness 0.91 0.76
Cognitive Dysregulation 0.66 0.70
Identity Problems 0.84 0.68
Affective Lability 0.69 0.70
Restricted Expression 0.45 0.78
Oppositionality 0.74 0.54
Anxiousness 0.96 0.86
Suspiciousness 0.61 0.45
Social Avoidance 0.76 0.69
Narcissism 0.60 0.47 0.45
Insecure Attachment 0.64 0.69
Stimulus Seeking 0.61 0.81
Callousness 0.88 0.66
Rejection 0.82 0.65
Conduct Problems 0.75 0.69
Restricted Expression 0.67
Intimacy Problems 0.93 0.75
Compulsivity 0.93 0.85
Suspiciousness 0.45