Personality and psychopathology: Genetic perspectives.

Abstract

Genetic factors exert an important influence on adult personality traits, accounting for anywhere between 30% and 60% of the variance. Heredity is also important for most forms of psychopathology and plays a major role in several theories that relate personality to psychopathology. Despite this, there has been surprisingly little multivariate genetic research reported on joint analyses of personality and psychopathology. The small amount of available data suggests that genes may account for over 50% of the observed correlation between neuroticism and state symptoms of anxiety and depression. The mechanisms behind such strong genetic correlations are crucial for understanding the causal relationship between a personality trait and a disorder because genetically influenced biological systems may operate as exogenous "third-party" factors that are responsible for what appear to be phenotypic cause-effect relationships. We illustrate how recent analytical advances in behavior genetics can use multivariate family data to address questions about the causal role of personality in psychopathology.

Common genetic risk factors for conduct disorder and alcohol dependence.

“…In many cases, especially when sample sizes are not particularly large, there may be insufficient power to detect an important genetic association between two traits in first degree relatives. 1\vin studies have added power for investigating the genetic covariation between traits because of the inclusion of MZ twins, who are genetically identical (Carey & DiLalla, 1994).…”

“…Of course, temporal ordering is a necessary but not sufficient condition for inferring that CD causes AD. Under certain restricted circumstances, for example, when one trait is largely influenced by genetic factors and the other is largely influenced by family environmental factors, structural equation models fitted to twin and family data can provide information about the direction of causation of the association between two traits (Carey & DiLalla, 1994;Duffy & Martin, 1994;Heath et al, 1993;Neale & Kendler, 1995). With data from the present study, these models were not able to resolve the direction of causation of the association between CD and AD.…”

Personality and the genetic risk for alcohol dependence.

“…Thus, the proportion of genetic covariation between AD and CD attributable to BU is (a X b)/(a X b + c X d). Similar models were used to estimate genetic correlations among AD, CD, and personality dimensions and to estimate the proportion of variation in AD or CD risk accounted for by other personality dimensions (see Carey & DiLalla, 1994;Neale & Cardon, 1992;or Slutske et aI., 1998, for more details about multivariate twin model fitting).…”

Delusional Drug Dependence- An Entity

“…aggressiveness, impulsivity, egocentrism and impersonal feelings and anti-social tendencies. 6 These are linked with the initiation and maintenance of drug use. 7 There is biological link between delusion and dependence.…”

“…4 Few studies have found a positive relationship between psychoticism and substance abuse. 5,2,3 High scorers on psychoticism exhibit some personality and behavioural traits such as impulsivity, aggressiveness, egocentrism and antisocial tendencies 6 and these traits have been shown to correlate with substance abuse. 7 Researchers have studied high levels of negative affect and an enduring desire for arousal and increased positive affect.…”