Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-27T12:13:59.540Z Has data issue: false hasContentIssue false
  • English
  • Français

The Heritability of Life Events: An Adolescent Twin and Adoption Study

Published online by Cambridge University Press:  21 February 2012

Heather R. Bemmels ,
S. Alexandra Burt ,
Lisa N. Legrand ,
William G. Iacono  and
Matt McGue
Heather R. Bemmels*
Affiliation:
Department of Psychology, University of Minnesota, Twin Cities Campus, Minneapolis, United States of America. hbemmels@tfs.psych.umn.edu
S. Alexandra Burt
Affiliation:
Department of Psychology, Michigan State University, East Lansing, United States of America.
Lisa N. Legrand
Affiliation:
Department of Psychology, University of Minnesota, Twin Cities Campus, Minneapolis, United States of America.
William G. Iacono
Affiliation:
Department of Psychology, University of Minnesota, Twin Cities Campus, Minneapolis, United States of America.
Matt McGue
Affiliation:
Department of Psychology, University of Minnesota, Twin Cities Campus, Minneapolis, United States of America.
*
*Address for correspondence: Heather R. Bemmels, Department of Psychology, University of Minnesota, 75 East River Road, Minneapolis, MN 55455.

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Although life events are often conceptualized as reflecting exogenous risk factors for psychopathology, twin studies have suggested they are heritable. We undertook a mixed twin/adoption study to further explore genetic and environmental contributions to individual differences in the experience of life events. Specifically, a sample of 618 pairs of like-sex adolescent twins, 244 pairs of like-sex adopted adolescent and young adult siblings, and 128 pairs of like-sex biological siblings completed a life events interview. Events were classified as independent (not likely to have been influenced by respondent's behavior), dependent (likely to have been influenced by respondent's behavior), or familial (experienced by a family member), and then summed to form three life event scales. Variance on the scales was assumed to be a function of four factors: additive genetic effects (a2), shared environmental effects (c2), twin-specific effects (t2), and nonshared environmental effects (e2). Data were analyzed using standard biometrical models. Shared environmental effects were found to be the largest contributor to variance in familial events (c2 = .71; 95% confidence interval of .65, .76); additive genetic effects were the largest contributor to dependent events (a2 = .45; CI = .31, .58); and nonshared environmental effects were found to be the largest contributor independent events (e2 = .57; CI = .51, .64). A significant twin-specific effect was also found for independent life events, indicating that twins are more likely to be exposed to such events than non-twin biological siblings. Findings are discussed in terms of their implication for understanding the nature of psychosocial risk.

Type
Articles
Information
Twin Research and Human Genetics , Volume 11 , Issue 3 , 01 June 2008 , pp. 257 - 265
Copyright
Copyright © Cambridge University Press 2008