The Genetic Overlap and Distinctiveness of Flourishing and the Big Five Personality Traits

The growing evidence that subjective well-being (SWB) produces an array of beneficial outcomes has increased requests for recommendations on how to promote it. Evidence that all of SWB’s genetic variance overlaps with personality led to the strong claim that it is a ‘personality thing’ and that personality is the strongest predictor of SWB. However, studies do not include a comprehensive assessment that reflects eudaimonic as well as hedonic SWB. We revisit the question of SWB’s complete overlap with personality employing the tripartite model—emotional, psychological, and social—of SWB that, together, reflect Keyes’ (2002) model of flourishing. Data are from the Midlife in the United States national sample of 1,386 twins. Analyses were done using Mx to test Cholesky decomposition models and a two latent factor common pathway model. One-third of the total (72 %) heritability of flourishing and 40 % of its environmental variability are distinct from the big-five personality traits. We also find a low phenotypic association (mean r = .22) between the three dimensions of SWB and big-five personality traits despite substantial shared genetic etiology. In addition to non-trivial amounts of distinctive genetic and environmental variance and low phenotypic correlation, we point to limited investigation of reciprocal causation of SWB and personality. Psychologist should not yet conclude that SWB is a ‘personality thing’ anymore than personality might be a ‘well-being thing’.     

Sources of structure: genetic, environmental, and artifactual influences on the covariation of personality traits

The phenotypic structure of personality traits has been well described, but it has not yet been explained causally. Behavior genetic covariance analyses can identify the underlying causes of phenotypic structure; previous behavior genetic research has suggested that the effects from both genetic and nonshared environmental influences mirror the phenotype. However, nonshared environmental effects are usually estimated as a residualterm that may also include systematic bias, such as that introduced by implicit personality theory. To reduce that bias, we supplemented data from Canadian and German twin studies with cross-observer correlations on the Revised NEO Personality Inventory. The hypothesized five-factor structure was found in both the phenotypic and genetic/familial covariances. When the residual covariance was decomposed into true nonshared environmental influences and method bias, only the latter showed the five-factor structure. True nonshared environmental influences are not structured as genetic influences are, although there was some suggestion that they do affect two personality dimensions, Conscientiousness and Love. These data reaffirm the value of behavior genetic analyses for research on the underlying causes of personality traits.     

Genetic and environmental influences on personality profile stability: unraveling the normativeness problem

The present study is the first to disentangle the genetic and environmental influences on personality profile stability. Spanning a period of 10 years, we analyzed the etiology of 3 aspects of profile stability (overall profile stability, distinctive profile stability, and profile normativeness) using self- and peer reports from 539 identical and 280 fraternal twins reared together. This 3-wave multirater twin design allowed us to estimate the genetic and environmental effects on latent true scores of the 3 aspects of profile stability while controlling for method effects and random error. Consistent biometric results were only found for profile normativeness, whereas overall and distinctive profile stability scores turned out to be biased. Over time, we found personality profile normativeness to be relatively stable. This stability was due to both stable genetic and nonshared environmental effects, whereas innovative variance was completely explained by nonshared environmental effects. Our findings emphasize the importance of distinguishing between the different aspects of profile stability, since overall and distinctive stability scores are likely biased due to the normativeness problem. Yet indicating a person's similarity to the average person, the normativeness of a personality profile itself has a psychological meaning beyond socially desirable responding.     

Genetic and Environmental Contributions to Individual Differences: The Three Major Dimensions of Personality

ABSTRACT This article deals with the contribution of genetic and environmental factors to individual differences in the three major dimensions of personality (Psychoticism, Extraversion, and Neuroticism) Twin studies indicate, and family studies confirm within limits, the strong genetic determination of these and many other personality factors, additive genetic variance accounting for roughly half the total phenotypic variance On the environmental side, shared family environment plays little or no part, all environmental effects being within-family Assortative mating, important in the formation of social attitudes, has little impact on personality Dominance may be important for Extraversion Epistasis (emergenesis) may account for the comparative low values of dizygotic (DZ) twins' correlations Evidence for differential heritability of traits is present, but not very strong It is concluded that behavioral genetics forms a vital part of the psychological understanding of the causes of individual differences in personality     

Delinquent peer affiliation and conduct problems: A twin study

Many putative environmental risks correlate with individuals' genotypes. The association between delinquent peer affiliation and conduct problems may occur because of shared genetic liability. Five hundred fifty three monozygotic and 558 dizygotic twin pairs, aged 11 to 18 years, were assessed for delinquent peer affiliation and conduct problems. The authors investigated whether genes contribute to both delinquent peer affiliation and the correlation between delinquent peer affiliations and conduct problems. Delinquent peer affiliation was influenced by genetic, shared environmental, and nonshared environmental factors; genetic factors also contributed to the correlation between delinquent peer affiliations and conduct problems, providing evidence for genotype-environment correlation. The magnitude of the genetic variance of conduct problems was contextually dependent on levels of delinquent peer affiliation and was greater at higher levels of delinquent peer affiliation.     

The genetic structure of Cloninger's seven-factor model of temperament and character in a Japanese sample

Theoretical assumptions regarding the genetic and environmental structure of personality proposed in Cloninger's seven-factor model of temperament and character were verified in a Japanese sample by using the twin method. The Temperament and Character Inventory (TCI) was administered to 296 twin pairs ranging in age from 14 to 28 years old. Among four temperament dimensions (novelty seeking [NS], harm avoidance [HA], reward dependence [RD], and persistence [PS]), HA and PS showed significant additive genetic contributions and no shared environmental effect, supporting the original theoretical assumption. NS and RD could be explained by either genetic or shared environmental factors with nonshared environment. All three character dimensions (cooperativeness [CO], self-directedness [SD], and self-transcendence [ST]) could be explained exclusively by additive contributions and no shared environmental effect. Multivariate genetic analysis indicated that there were no significant associations between NS, HA, and RD, as the theory predicts, and the genetic components of PS, SD, and CO were derived from those of the temperament dimensions. The fourth genetic component, which had a substantial load specifically on ST and overlapped with PS, was identified. Although most of the nonshared environmental effects were trait-specific, the phenotypic correlation between NS and HA could be explained by nonshared environmental overlap.     

Genetic and Environmental Pathways Underlying Personality Traits and Perceived Stress: Concurrent and Longitudinal Twin Studies

The present study examined the genetic and environmental etiology underlying the Big Five personality traits and perceived stress, concurrently and longitudinally. In study 1, we used the twin sample from the National Longitudinal Study of Adolescent to Adult Health (Add Health IV) data. The results indicated that about 70% of the association between the Big Five personality traits and perceived stress was due to genetic influences. In study 2, we used the twin sample from the Midlife in the United States Survey (MIDUS I and II) to examine the genetic and environmental influences underlying the longitudinal relations between the Big Five personality traits and perceived stress. The results suggested that continuity in perceived stress was primarily accounted for by genetic influences, and changes in perceived stress were mainly due to nonshared environmental influences. The continuity in the association between the five personality traits and perceived stress was largely accounted for by genetic factors, and nonshared environmental factors made greater contributions to changes in the association between personality traits and perceived stress. Among the Big Five personality traits, the genetic components in conscientiousness and neuroticism made substantial contributions to the genetic link between personality traits and perceived stress across both studies. Copyright © 2017 European Association of Personality Psychology     

Normal and abnormal personality traits: evidence for genetic and environmental relationships in the Minnesota Study of Twins Reared Apart

ABSTRACT Recent studies have demonstrated substantial correlations between normal and abnormal personality traits. Yet little is known about how these correlations are mediated genetically and environmentally: Do normal and abnormal personality traits stem from the same underlying genes and environments? We addressed this question using data from 128 monozygotic and dizygotic twin pairs in the Minnesota Study of Twins Reared Apart (MISTRA). Additive genetic and nonshared environmental correlations between scales of the Minnesota Multiphasic Personality Inventory (MMPI)—an index of abnormal personality—and the Multidimensional Personality Questionnaire (MPQ)—an index of normal personality—were estimated. Results indicated that phenotypic correlations between normal and abnormal personality were mediated by genetic as well as environmental factors, although the magnitude of genetic mediation tended to be larger overall. Moreover, the patterns of phenotypic, genetic, and environmental relationships among the scales were similar, suggesting that influences on normal and abnormal personality act through systems common to both. It is suggested that future research focus on the neurogenetic substrates of these shared systems and how dysfunction in these systems influences development of disordered personality.     

Nonshared environment: a theoretical, methodological, and quantitative review

When genetic similarity is controlled, siblings often appear no more alike than individuals selected at random from the population. Since R. Plomin and D. Daniels' seminal 1987 review, it has become widely accepted that the source of this dissimilarity is a variance component called nonshared environment. The authors review the conceptual foundations of nonshared environment, with emphasis on distinctions between components of environmental variance and causal properties of environmental events and between the effective and objective aspects of the environment. A statistical model of shared and nonshared environmental variables is developed. A quantitative review shows that measured nonshared environmental variables do not account for a substantial portion of the nonshared variability posited by biometric studies of behavior. Other explanations of the preponderance of nonshared environmental variability are suggested.     

Insecure attachment and personality disorder: a twin study of adults

This study used 239 twin pairs from a volunteer community sample to investigate how anxious and avoidant attachment are related to personality disorder (PD). Factor analysis showed that self‐reported anxious attachment and 11 PD scales from the Dimensional Assessment of Personality Problems loaded onto one factor (emotional dysregulation), and avoidant attachment and four PD scales loaded onto a second factor (inhibitedness). Biometric models indicated that 40% of the variance in anxious attachment was heritable, and 63% of its association with corresponding PD dimensions was attributable to common genetic effects. Avoidant attachment was influenced by the shared environment instead of genes. Correlations between avoidance and corresponding PD dimensions were attributable to experiences in the nonshared environment that influenced both variables. Copyright © 2006 John Wiley & Sons, Ltd.     

Heritability of the Big Five Personality Dimensions and Their Facets: A Twin Study

ABSTRACT The genetic and environmental etiology of the five-factor model of personality as measured by the revised NEO Personality Inventory (NEO-PI-R) was assessed using 123 pairs of identical twins and 127 pairs of fraternal twins. Broad genetic influence on the five dimensions of Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness was estimated at 41%, 53%, 61%, 41%, and 44%, respectively. The facet scales also showed substantial heritability, although for several facets the genetic influence was largely nonadditive. The influence of the environment was consistent across all dimensions and facets. Shared environmental influences accounted for a negligible proportion of the variance in most scales, whereas nonshared environmental influences accounted for the majority of the environmental variance in all scales.     

Examining transactional influences between reading achievement and antisocially-behaving friends

The association between poorer academic outcomes and having antisocial friends is reliably demonstrated yet not well understood. Genetically sensitive designs uniquely allow for measuring genetic vulnerabilities and/or environmental risk in the association of antisocial friend behavior and poor school achievement, allowing for a better understanding of the nature of the association. This study included 233 pairs of twins from the Florida Twin Project on Reading. First, the role of antisocial friends as an environmental moderator of reading comprehension was examined. Antisocial friends significantly moderated the nonshared environmental variance in reading comprehension, with increased variation at lower levels of association with antisocial friends, with niche-picking indicated. Second, the role of reading comprehension as an environmental moderator of antisocial friends was examined. Reading comprehension significantly moderated the nonshared environmental variance in associating with antisocial friends, with increased variance at lower levels of reading comprehension and indication that common genetic influences contributed to higher reading achievement and better-behaved friends. In total, these results suggested reciprocal influences between reading achievement and antisocially-behaving friends. The impact of antisocial friends appeared to be limited in the extent to which they can undermine reading achievement, and high reading achievement appeared to support less association with antisocial friends.     

Examining genetic and environmental effects on reactive versus proactive aggression

This study compared the contribution of genes and environment to teacher-rated reactive and proactive aggression in 6-year-old twin pairs (172 pairs: 55 monozygotic girls, 48 monozygotic boys, 33 dizygotic girls, 36 dizygotic boys). Genetic effects accounted for 39% of the variance of reactive aggression and for 41% of the variance of proactive aggression. The remainder of the variance was explained by unique environmental effects. Genetic as well as unique environmental effects were significantly correlated across reactive and proactive aggression (genetic correlation = .87, environmental correlation = .34), but this overlap was largely due to a common underlying form of aggression (i.e., teacher-rated physical aggression). Once common etiological factors due to physical aggression were accounted for, reactive and proactive aggression shared no other genes and only a few environmental influences, although additional specific genetic and environmental effects were observed for both reactive and proactive aggression. These specific effects indicate that both reactive and proactive aggression may be influenced mostly by socialization experiences that are specific to each type of aggression and only to a very small degree by specific genes.     

Subjective Wellbeing as an Affective-Cognitive Construct

The affective content of Subjective Wellbeing (SWB) was investigated in two separate studies. Study 1 involved a representative sample of 478 participants from across Australia aged between 18 and 72 years. This study tested the circumplex model of affect and then determined the minimum set of affects that explain variance in SWB. The model was supported, with most affects congregated around the valence axis. Overall, 64% of the variance in SWB was explained by six Core Affects, indicating that SWB is a highly affective construct. Study 2 tested the relative strength of Core Affect (content, happy and excited), in three separate models of SWB incorporating cognition (seven discrepancies) and all five factors of personality. Using a sample of 854 participants aged been 18–86 years, structural equation modeling was used to compare an affective-cognitive driven model of SWB, with a personality driven model of SWB and a discrepancy driven model of SWB. The results provide support for an affective-cognitive model which explained 90 percent of the variance in SWB. All models confirm that the relationship between SWB, Core Affect and Discrepancies is far stronger than the relationship between personality and SWB. It is proposed that Core Affect and Discrepancies comprise the essence of SWB. Moreover, Core Affect is the driving force behind individual set-point levels in SWB homeostasis.     

Genetic and Environmental Influences on Personality: A Study of Twins Reared Together Using the Self- and Peer Report NEO-FFI Scales

ABSTRACT Previous behavior-genetic research on personality has been almost exclusively based on self-report questionnaire measures. The purpose of this research was to measure personality constructs via self- and peer reports on the items of the NEO Five-Factor Inventory (Costa & McCrae, 1989). The sample included 660 monozygotic and 200 same sex and 104 opposite sex dizygotic twin pairs. We collected self- and two independent peer reports for each of the twins. Our analysis of self-report data replicates earlier findings of a substantial genetic influence on the Big Five (h²= .42 to .56). We also found this influence for peer reports. Our results validate findings based solely on self-reports. However, estimates of genetic contributions to phenotypic variance were substantially higher when based on peer reports (h²= .51 to .81) or self- and peer reports (h²= .66 to .79) because these data allowed us to separate error variance from variance due to nonshared environmental in-fluences. Correlations between self- and peer reports reflected the same genetic influences to a much higher extent than identical environmental effects.     

Common Genetic and Environmental Influences on Major Depressive Disorder and Conduct Disorder

The evidence for common genetic and environmental influences on conduct disorder (CD) and major depressive disorder (MDD) in adolescents was examined. A sample of 570 monozygotic twin pairs, 592 dizygotic twin pairs, and 426 non-twin siblings, aged 12-18 years, was recruited from the Colorado Twin Registry. For the past year data, there was a significant correlation between the genetic influences on MDD and CD and, for the lifetime data, there was a significant correlation between the genetic influences on MDD and CD, and a significant correlation between the nonshared environmental influences on MDD and CD. Our results suggest that some genetic factors will increase an individual's vulnerability to both MDD and CD in adolescence.     

Can chimpanzee (Pan troglodytes) happiness be estimated by human raters?

The authors investigated measurement of chimpanzee “happiness” based on the human trait of subjective well-being (SWB). Zoo workers at 13 zoos used a 7-point scale to rate 128 chimpanzees on four items related to their SWB. The items included assessment of pleasure derived from social interactions, balance of positive and negative moods, success in goal attainment, and the desirability of being a particular chimpanzee. The four items formed a single factor that had excellent interrater reliability and was temporally stable. Examination of the relationship between chimpanzee SWB and six chimpanzee personality factors, five of which resembled the human Big Five factors, showed that chimpanzee SWB varied positively with Dominance, Extraversion, and Dependability factors. SWB was negatively correlated with frequency of submissive behaviors. Age and sex were not significantly related to SWB.     

The extended genotype: the heritability of personality accounts for the heritability of recalled family environments in twins reared apart

Abstract How are retrospective accounts of family rearing environments linked to adult personality? We addressed this question by measuring both domains in a sample of 180 reared‐apart twins. Twins completed extensive measures of rearing environments (the Minnesota‐Briggs History Record, the Block Environmental Questionnaire, the Family Environment Scale, and the Physical Facilities Questionnaire) and an omnibus measure of adult personality (the Multidimensional Personality Questionnaire). Retrospective accounts of family environments were partially heritable and all the heritable variance in environmental measures could be accounted for by heritable variance in personality. In addition, differences between twins in their accounts of their rearing environments (nonshared environmental factors) were not significantly linked to differences between twins in their personalities. Hence, family environmental measures appear to be heritable because personality genes influence the way people shape and recall their rearing environments. In addition, differences in reared‐apart twins' retrospectively recalled rearing environments appear to have little impact on differences in their personalities in adulthood.     

Big Five personality traits: Are they really important for the subjective well‐being of Indians?

This study empirically examined the relationship between the Big Five personality traits and subjective well‐being (SWB) in India. SWB variables used were life satisfaction, positive affect and negative affect. A total of 183 participants in the age range 30–40 years from Pune, India, completed the personality and SWB measures. Backward stepwise regression analysis showed that the Big Five traits accounted for 17% of the variance in life satisfaction, 35% variance in positive affect and 28% variance in negative affect. Conscientiousness emerged as the strongest predictor of life satisfaction. In line with the earlier research findings, neuroticism and extraversion were found to predict negative affect and positive affect, respectively. Neither openness to experience nor agreeableness contributed to SWB. The research emphasises the need to revisit the association between personality and SWB across different cultures, especially non‐western cultures.     

Personality stability in late adulthood: a behavioral genetic analysis

A sample of 833 twins from the Minnesota Twin Study of Adult Development and Aging completed the Multidimensional Personality Questionnaire (MPQ; Tellegen, 1982) twice, averaging 59.4 (sd=9.7) years of age at first and 64.4 (sd=10.2) years of age at second testing (average retest interval 5.0 years, sd=2.36, range 1.0-10.4 years). Both means and standard deviations of scale scores were extremely stable from first to second testing. In addition, sample participants tended to retain their rank order on the scales (average r=.76 across scales). Bivariate biometric analyses showed that the genetic influences on most of the scale scores were almost perfectly correlated across the two waves (range .95 to 1.00). The nonshared environmental influences were also highly correlated across the two waves (range .53 to .73). Models specifying identical variance components at the two time points and fixing the genetic correlation to 1.00 provided improved fit. The results suggest that the high stability of personality in later adulthood has a strong genetic foundation, supplemented by stability of environmental effects.