Genetic and environmental contributions to cannabis dependence in a national young adult twin sample

Abstract

There was consistent evidence that genetic risk factors are important determinants of risk of cannabis dependence among men. However, it remains uncertain whether there are genetic influences on liability to cannabis dependence among women.

Childhood sexual abuse and risks for licit and illicit drug-related outcomes: a twin study

“…The abuse assessment, though diagnostic, would miss cases with maladaptive use limited to non-assessed categories. The non-diagnostic dependence assessment has excellent sensitivity and specificity for DSM-IV drug dependence (Lynskey et al 2002(Lynskey et al , 2003. We combined abuse and dependence within each drug class as in Lynskey et al (2003).…”

Early childhood behaviours, schooling and labour market outcomes: estimates from a sample of twins

“…This has long been recognised in the behavioural genetics literature (e.g., Lynskey et al 2002. The potential for childhood behaviours to impact on an individual's outcomes in the labour market has also been examined in several studies (e.g., Farmer 1995, Fergusson and Horwood 1998, Gregg and Machin 2000, Feinstein 2000.…”

Linkage scan for quantitative traits identifies new regions of interest for substance dependence in the Collaborative Study on the Genetics of Alcoholism (COGA) sample

“…In adults, genetic factors contribute to 40-60% of the total variance in risk for alcohol dependence (Dick et al, 2006;Heath et al, 1997;Kendler et al, 1994;Prescott et al, 1995;Tsuang et al, 2001), while for illegal drug dependence, estimates of heritability range from 35-75% (Kendler et al, 2003a;Lynskey et al, 2002;Tsuang et al, 1996;Tsuang et al, 2001;van den Bree et al, 1998). Results from multivariate twin analyses suggest that (i) the liability for dependence on various illicit drug classes is governed, in part, by common genetic factors (Kendler et al, 2003a;Tsuang et al, 1998), and (ii) a significant proportion of the genetic influences on alcohol and illicit drug dependence may be overlapping (Bierut et al, 1998;Kendler et al, 2003b;McGue et al, 2000;Tsuang et al, 2001).…”